Home

Windows

1. 0 es 1 3 1 1 3 1 PADU 1 3 2 1 3 2 File management 2 ccc ehh 1 3 2 LOA CCS E B 1 3 2 1 3 2 2Make a copy ofa model 2 3cecd4hed4ewsebe sae ss eds baeusebet eases be Joes QURE EE WE 1 3 3 132 3 COPY 10 anolher OUCOO asgi waa arene bed ated doo et dee ao dees one aes ated aes 1 3 4 1 3 2 4 Copy from another directory 0 ee ene 1 3 5 1 3 3 Change current directory ias cre drpm obonkbacebouneds EI IESTS 1 5 x oe 1 3 5 1 3 4 Copy to a ZIP We 4 1 3 6 1 3 5 UnZIP a MEMEMEMMMRCTM 1 3 6 1 3 6 Display model file names 0 cc en 1 3 7 159 7 Add a file to model list llle III 1 3 8 1 3 8 Recover model geometry ce eee hrs 1 3 8 EE o Arr 1 4 1 1 4 1 deti m 1 4 1 1 4 2 Mte c 1 4 1 1 4 3 ziildo I M CHR ares a eh ek Soe ee ee eer dee ee 1 4 2 1 4 4 gcc m det oe Ber ce hehe deb ed Beet ERRIRE R hee ether eerageesesense 1 4 3 ko UNGS TP 1 5 1 1 5 1 FOOUNG OCSI vvv 1 5 1 1 5 2 User steel section table 0 0 0 n 1 5 1 1 5 3 Compute section properties 0 0 rh 1 5 1 1 5 4 Combine results of two projects 0 0 ce ee e 1 5 2 1 5 5 Recreate the model list 2 0 0 ene e 1 5 2 1 5 6 STAAD File CONVEISION xad ano
2. For all other STRAP properties the program will ignore the STRAP properties and must be instructed to select the lightest suitable section from a user defined list or to check a specified section The cases are e dimension section types Rectangular and unsymmetric shape shape and T shape sections e properties defined with the section constants A l option tapered sections defined with properties other than acceptable built up shapes e if the property was defined with a steel section not in the current model table A warning will be displayed at the start of the program For example The following properties can not be solved not in section table rectangular section rectangular section end sections not steel shapes Da oy I When selecting a suitable section the program checks sections from a specified list beginning from the lightest one until it finds the first adequate section If the program had to search the complete master table when designing each member in the model the selection process would be very time consuming Version 12 5 7 2 12 06 STRAP 7 3 Creating a Steel Structure from the STRAP Model Member selection is automatic the program designs all beams in sequence without prompting for information Therefore all data and information relevant to the design of the members as required by the Code must be entered before member selection begins In many cases the model geomet
3. The program also handles intersections between lines between elements and between lines and elements Version 12 5 1 6 1 12 06 STRAP Note DXF space models create STRAP space models DXF plane models all Z coordinates 0 create STRAP plane frames The program defines element local axes according to the STRAP defaults The program creates quad finite elements wherever possible non planar quads are divided into two triangles Each 3DFACE element polygon mesh or polyface mesh surface generates one STRAP finite element Double lines are treated as single lines Concave elements defined by lines 3DFACE polygon mesh or polyface mesh are ignored When creating finite elements the program accepts only quads or triangles Nodes will be created at intersection points even if no elements are generated Version 12 5 1 6 2 12 06 STRAP 1 7 Getting Started This section is intended mainly for engineers who have no previous experience in the use of computers for structural analysis or who are unfamiliar with the finite element method The engineer must prepare a computer model of the structure The model consists of a series of elements joined at points called nodes or joints STRAP uses two types of elements Beam elements Beams are one dimensional elements that are used to model structural members that can be modeled by a line beams columns bars etc Beam elements always give accurate results i e if a m
4. When calculating the maximum response the total response usually cannot be obtained simply by adding the maximum responses of the individual nodes because these maxima usually do not occur at the same time Version 12 5 6 1 12 06 STRAP The user may select one of the following methods to estimate the maximum total response from the maximum calculated modal values e SRSS Sum of Root of the Sum of the Squares method e CQC Complete Quadratic Combination In both methods the program calculates the response for each mode separately and then combines them according to a formula that accounts for the fact that when one mode achieves its maximum response the responses of the other modes are less than their individual maxima Note that each maximum response is calculated separately e g the maximum moments are calculated as the RSS CQC of the moments from the individual mode shapes and not as the moments resulting from the RSS CQC deflections of the model e SHSS square root of sum of squares The estimated response R force displacement etc at a specified coordinate may be expressed as R JER where Ri is the corresponding maximum response of the ith mode at the coordinate e CQC complete quadratic combination The estimated response may be expressed as p M M 5 LLR P d i 1j 1 where the cross modal damping coefficient o may be approximated by Bg un r 2 F 1 y AETA where r ojoi ratio
5. 1 Divide an existing beam into two or more beams if intermediate nodes are located along the length SP ofthe beam Inl opecify or revise the direction of the local axes for beams axes When a stage other than Whole model is the current stage beams may be removed or restored Different properties releases and offsets may be defined Version 12 5 2 12 12 06 STRAP 2 4 Elements Define quadrilateral or triangular elements by specifying location designate the end nodes e properties define the element thickness e material elements may be isotropic or orthotropic e localaxes specify the local x3 axis direction When Elements are selected in the geometry Main Menu the following options are available g Define one triangular element by identifying its end nodes Ian Define one quadrilateral element by identifying its end nodes Define a chain of triangular elements where only the third node of successive elements need be defined the program uses two nodes of the previous element common to both elements to complete the new triangle E follo m Define a chain of quadrilateral elements where only the third and fourth nodes of successive d elements need be defined the program uses two nodes of the previous element common to both elements to complete the new quadrilateral define a base line consisting of a chain of nodes and a height line also a chain of nodes that starts pud at one end of the
6. A list box displays a column of available choices A drop down list box displays only the current option along with an arrow at the end of the line For example the Result type option in the above dialog box is displayed as Element results contour map B When the arrow button is pressed the list box opens up to Element results contour map B Geometry Results at element centers Element results contour map Element results along a line Displacements The current option is highlighted Option button Option buttons represent a list of mutually exclusive options i e only one of them can be selected In our dialog box example we can select to display the results for either a load case load combination or an envelope of cases combinations The selected option is highlighted by a black dot in the button In our example the program will display the result for a load case To select a new option place the arrow on the option you want and click the mouse button Version 12 5 1 9 2 12 06 STRAP Check box Check boxes represent options that can be turned on or off When the option in the check box is turned on the box is displayed as IV In our example the result diagrams will be hatched To revise the option place the arrow on the check box and click the mouse button Text box A text box is a rectangle into which you can type information In the dialog box above the number of contour lines is d
7. ATERT SIRAP for Windows SIRUCTURAL ANALYSIS PROGRAM USER S MANUAL Version 12 5 December 2006 STRAP Blank page Version 12 5 ii 12 06 STRAP Disclaimer The STRAP programs have been written by a team of highly qualified engineers and programmers and have been extensively tested Nevertheless the authors of the software do not assume responsibility for the validity of the results obtained from the programs or for the accuracy of this documentation The user must verify his own results The authors remind the user that the programs are to be used as a tool for structural analysis and that the engineering judgement of the user is the final arbiter in the development of a suitable model and the interpretation of the results Windows is a registered trademark of Microsoft Corp AutoCAD is a registered trademark of Autodesk Inc Version 12 5 lii 12 06 STRAP Blank page Version 12 5 iV 12 06 STRAP Table of Contents 1 General a ee a ee ee ee 1 0 1 L1 Installing the Program 2460660650000 cid ddan tenacewwe cant inte dane caweeanianee eae 1 1 1 1 1 1 lv T T 1 1 2 12 RUNNING ine program sezaeazackubmorcacirubes edm acEuUR a REOR E ebd ace ws Rcx rm Eee 1 2 1 1 2 1 Define a new model llllleleeeeee leen 1 2 2 1 2 2 Amend rerun an existing model 0 00 ccc cee eee n 1 2 3 1 3 Main menu File options
8. Highlight the commands click and hold the mouse drag the cursor then select Edit Copy in the menu bar Press Alt Tab to return to STRAP Combinations definition 1 Ho cp go 171 004 2 1 00 OK Cancel Copy Cut Paste e place the anywhere on the line where the command is to be written and click the mouse if you select a line with an existing combination then the command will be inserted above the line Paste e Click the button Note that multiple commands may be cut and pasted at the same time Version 12 5 1 11 4 12 06 STRAP 2 Geometry Main Menu The program displays the geometry definition screen including the current model if an existing model was selected The geometry definition options are displayed at the right hand side of the screen 7 To define node coordinates Refer to 2 1 node Y To define restrained supports and rigid links Refer to 2 2 To define beam elements including location of the beam between two nodes properties materials pinned connections rigid offsets local axes directions Refer to 2 3 To define quadrilateral and triangular finite elements including location of the element properties materials including orthotropic Refer to 2 4 To define elastic supports Refer to 2 5 E Le To duplicate a portion of the model at another location including nodes elements and properties The copied portion of the model may be
9. Version 12 5 2 4 12 06 STRAP from line select nodes 1 and 2 the new node is on the line perpendicular to line 1 2 drawn from node 1 according to one of the following options Node location Ea Define the node location on the perpendicular as follows Distance from line Note distance is positive at left side of the line ata specified distance from node 1 Note that a positive value is to the left when standing at 1 and looking towards 2 the example above shows a negative value at the intersection with another line defined by two additional nodes 3 and 4 in the example above at the intersection with an arc defined by three additional nodes C Intersection with a line C Intersection with an arc OK Cancel e DXF points This option is displayed only if a DXF drawing has been added to the display background Iv ONLY the end points of DXF lines may be selected as node locations I the DXF end points will not be highlighted with the m e Grid lines Define a node at the intersection point of any two grid lines For example c 8 Note that this option not available when a background DXF drawing is T displayed e More Define a node in the Following way intersection of a plane and a line Plane defined by 3 nodes Line defined by 2 nodes Select additional nodes Modes will be created at the intersection of parallel lines through those nodes and the plane Define Intersec
10. Define the start and end nodes of the line as explained in 2 1 2 Line Equal Point to the intermediate nodes along the line as follows The moves along the line joining the start and end nodes The dialog box at the bottom of the screen is oi OK End Cancel Screen where dD gt distance from the last node defined on the line as measured along the line dX1 dX2 dX3 gt distance from the last node defined on the line global coordinates D gt distance from start node as measured along the line D dx2 0 H ax3 dD dx pii Note that dX1 or dX2 the closest to the line and not dD is updated at the Step rate a feature that is very convenient when only the projected spacings of a diagonal line on a global axis are known In many cases it may be more convenient to type the spacing directly in the text boxes rather than by continuously adjusting the Step for each node Example move the A to the location of Node 1 and click the mouse move the to the location of node 4 dX1 8 0 dX2 2 0 and click the mouse move the h along the line until dX1 3 0 is displayed click the mouse node 2 is created move the h along the line until dX1 2 5 is displayed click the mouse node 3 is created move the amp outside the line and click the mouse Version 12 5 2 7 12 06 STRAP Additional options refer to 2 1 1 Define with same coordinates as existing node Define end nod
11. Plane parallel xe to 1 x5 Elements perpendicular to the X1 X2 plane e X direction parallel to the line of intersection of the element plane with a plane parallel to the X1 X2 global axis In certain cases the default axes may not give the required results For example reinforcement in concrete slabs is not parallel to the global axes e x3 local axis directions are not consistent in cylindrical or spherical models Version 12 5 5 3 12 06 STRAP You may revise the result coordinate system for each quadrilateral and triangular finite element Default This option restores the default element result axes for the selected elements The element local axes The result coordinate system of each selected element will be identical to its local coordinate system i e X xX1 Y x2 Z 4x3 Examples Grid For elements 1 to 9 the reinforcement is rotated 45 from X1 i e parallel to the element boundaries and so the moments should be relative to the local axes By default the results will be relative to the global axes e Space frame The default Z axis directions are displayed above note that some point inwards towards the centre of the cylinder while the rest point outwards Use z this option to define a consistent direction for all elements 7 v Z Note that this option may lead to misleading and inconsistent results For example e Triangular elements ia 27 JB The results f
12. Operating System Windows 98 2000 NT XP Capacity Regular Enhanced Professional Program Capacity Version Version Version Maximum node number 1000 2500 32000 Maximum element number 2500 32000 32000 Maximum property group number Maximum number of loading cases 1000 Maximum number of combinations 1000 Maximum number of load cases per combination 1000 Maximum number of load groups 100 Maximum number of load cases per group 1000 Maximum DOF bandwidth after optimization 16000 Maximum number of mode shapes Note e STRAP may crash if other programs with large memory demands e g AutoCAD are running simultaneously Version 12 5 A 1 12 06 STRAP A2 Printing the Manual The entire STRAP manual is supplied with the program in PDF Adobe Acrobat format files All text in the program Help is included in the printed manual The files are located on the installation CD in folder STRAPWMDOC To print the manual use the Adobe Acrobat Reader program copy from the STRAP Installation CD or download from the Adobe Internet site The manual is contained in a series of files File STRAP PDF CODE UK PDF CODE US PDF CODE CDN PDF CODE EUR PDF CODE IND PDF CODE CHN PDF FOUND PDF CROSEC PDF CMD MODE PDF VERIF PDF DEMO USA PDF DEMO MTR PDF SHORT MAN PDF SMAN EX PDF Version 12 5 Contents STRAP manual except for the following BS5950 BS8110 AI
13. The program displays the numerical value of the deflection in the form ddd 10 where dad is written adjacent to the beam and the factor 10 appears at the bottom of the screen Examples 51 written adjacent to the element Values are 1043 at the bottom of the screen deflection 51 1000 0 051 current length units 272 written adjacent to the element Values are 1042 at the bottom of the screen deflection 272 100 2 72 current length units 5 4 Tabular results 5 4 1 Tables Sign Conventions The tabular results use a mathematical sign convention as opposed to the standard engineering sign conventions the sign of the results may often be opposite to what is expected and so the user must understand the conventions in order to correctly interpret the results 5 4 1 1 Sign Conventions Beams Member results are listed at nodes JA JB of each element Results are relative to the local coordinate axes The positive sign conventions are xz j Wo direction of positive mament Vg LX AXIAL om o AXIAL JA 7 n Pi me positive directi eed Fight hand p i I Med Moments M2 M3 MT The direction of a positive moment is determined by a right hand rule The thumb points in the positive direction of the local axis about which the moment acts and the other fingers all curl in the direction of the positive moment In the following example engineering negative moments act at both ends of the beam how
14. from STRAP INI Reset all values 1 4 1 Setup Colors You may specify the permanent screen colors for background e graphic lines e g beams elements various loads etc e text associated with each graphic line colors for contour map fills 1 4 2 Miscellaneous Units Set the default input and result force and length units for all new models Default units definition Length units Weight units S meter ton C millimeter C kiloNewton C centimeter C kilogram C inch C gram C feet CC kip C pound Default results units Cancel Set the default input and result units for all new models if the default units are revised at the start of the geometry definition the revision will apply only for that particular model Materials The properties of 10 materials are permanently stored in the program Four of these materials are user defined materials These 10 properties will be displayed when the Materials option is selected in beam or element property definition The properties of all 10 materials may be edited Version 12 5 1 4 1 12 06 STRAP The properties are e Modulus of elasticity e Poisson s ratio Density e Thermal expansion coefficient 1 Celsius or 1 Fahrenheit Units e Specify the units for modulus of elasticity and density in the list boxes at the top of the screen The thermal coefficient may be defined according to either unit However the
15. is displayed for more detailed Hein Jump Single Beam Define one beam element by identifying its end Hotspot nodes Bi Define a series of beams all lying on a straight line The beams are defined by identifying the nodes at the start and the end of the line the program automatically lacates all intermediate nodes and connects them with beams Pop up Delete Delete a beam already defined Del Version 12 5 1 9 4 12 06 STRAP The following Help options are available e Jumps Hotspots and Pop ups These hyperlink options enable you to jump directly between related topics The r automatically changes to a when it moves over a hyperlink location Click the mouse to display the Help for the related topic Pop up text is written over the existing help topic and is removed from the screen by clicking the mouse Pop up links are underlined with a dashed line Option buttons Eontents The Table of Contents of the entire STRAP User s Manual is displayed on the screen Inde Locate information on any topic identified by a keyword Back Return to the topic previously displayed Clicking this button allows you to retrace your path through the Help topics you have already displayed Print To print the topic currently displayed e a i Display the previous following topic in a series of related topics The buttons are grayed out when you reach the first last topic in a sequence Banner butto
16. or area was defined for the model The ratio between the largest and smallest values should not exceed 1 10E8 n plate bending elements the element thickness is large relative to the element dimensions note that only the Reactions are affected moments and deflections are accurate Results Sorted by Elements Nodes The reactions are printed only at nodes that were defined as restraints and so the inaccuracies described above will not be apparent Note that the max min reactions are the maximum and minimum numerical reactions at the supports Version 12 5 5 13 12 06 STRAP Blank page Version 12 5 5 14 12 06 STRAP 6 Dynamic analysis This dynamic analysis module analyses the modal shape of the model solves for the natural frequencies and the corresponding mode shapes calculates the earthquake response and the resulting moments and forces in the model based on the calculated mode shapes and Code related factors calculates the time history response for forced vibrations 6 1 Mode Shape and Natural Frequency Analysis This dynamic analysis module analyses the modal shape of the model The program solves for the natural frequencies and the corresponding mode shapes The program solves the problem of undamped free vibrations This involves the solution of the generalized eigenvalue equation K M 5t where K stifness matrix M Mass matrix t eigenvalue matrix corresponding eigenvec
17. 235 0 000 0 000 O000 1 263 MAK 0 089 2 450 0 000 DO Or 0 000 1 333 COMB z 1 0 0 T MIN 0 076 1 235 0 000 0 000 0 000 0 135 COME 2 T 1 i 1 where Axial axial force along beam x1 axis For trusses only the result at JA is displayed the value at JB may be different if an intermediate axial load is applied but the result will not be displayed V2 shear force parallel to the beam x2 axis V3 shear force parallel to the beam x3 axis MT torsion moment about the beam local x1 axis M2 bending moment about the beam local x2 axis M3 bending moment about the beam local x3 axis Refer also to 5 4 1 1 Sign conventions beams If the End results and max in span option is selected the display is z 5 0 089 0 765 0 000 O0O00 0 000 0 325 FR 0 45 0 044 2 325 6 0 089 1 235 0 000 O000 0 000 1 263 where FR fraction of span length from JA at which the maximum intermediate moment occurs Note e The intermediate moments are calculated at 1 20 intervals and at concentrated load locations e The sign of the intermediate moment and shear is relative to the sign at JA e he intermediate shear value displayed is at the same point as the maximum moment e An intermediate value is displayed only if the maximum positive moment or maximum negative moment are not at the end supports e All intermediate values displayed are included in the following MAX MIN value searches When calculating the MAX MIN results the program
18. 9 10 Print edit drawing The drawing editor module contains options for modifying and adding text and lines to the graphic displays in STHAP All drawings may be printed plotted The main features of the program are e he module can differentiate between the different types of text and lines node numbers beam numbers titles etc Hence a property size color etc can be modified at the same time for all texts in a type e he module recognizes the paper size of the selected printer plotter and allows several drawings to be arranged on the page New text Revise text Type and locate a line of text on the drawing according to the text parameters e Revise the text or properties of selected text select text using the standard text selection options revise the text or any of the properties size angle pen width color frame Version 12 5 1 9 8 12 06 STRAP m concrete India edit drawing ME E File oom Edit Tex Line Help Size 25 Specify parameters before ar during typing Ange n width 0 color Frame Justify hor Left vec Top Testina Cancell Move Type in text here Text is written immediately on screen Click ta move text while typing Select text Select one or more texts using any of the following options Select by window Cancel Select by polygon Select all texts Multiple selection Limit selection by type e Select tex
19. SIE aS UE VOR OR EE at br E D Gs 1 11 1 1 11 1 Batch mode Geometry 0 0 eee eens 1 11 1 1 12 Bach Mode Loads eeu s ode mte D OE e T E OG E Re Ed Ou fuer Dg pads dans iE EE 1 11 3 1 11 3 Batch mode Combinations 0 0 0 0 ccc eee es 1 11 4 2 Geometry Main Menu 0 00 cee ee 2 1 2A NOUBS 22 5s xe 1h89 OSCURO E e IE RC D IR eae X Un e sweet ones X8 n elo nn REN I es 2 2 2 1 1 DINGIS NOUS rr 2 2 2 1 2 Line of Nodes Equal Spacing 0 cc eee eee eae 2 6 2 1 3 Line of Nodes Unequal Spacing 2 0 eee eee 2 7 2 1 4 Nodes Coordinate system 0 0 ce eee eee ees 2 8 PLEBE LC QCIDCHESERERTERTTOI TITRES 12 2 017 201 1017 117 heute cia eonteecee ens 2 11 2 39 Beads 2 225920 2 M25 0 2 92 20 0 229 tees eee rd Uca ua NS aru M UR RE RUE MU E ee 2 12 UGOME a Aer 2 13 2 9 OPOS 22 53 159 33 92 025 9 2 1051 9 29 32 9 892 9 9 9 8 A0 9 2 73 18 5 9 595 Rid x ees a Edu 2 15 20 CODY re eee 2 16 2 Solidelemelils us ssikc otc DR 0 d Rc D 8i b AN 8 0 seed ae eee ewe 2 17 Version 12 5 vi 12 06 STRAP 20 Wall EISIeHIS o2 4 16 008 9 0 scito 0 bte 10a 2 hae bse hoe eee ee oes 2 18 2 9 Sub model eceeeeeeeee eee mnn 2 20 2 10 Se e 2522 532 1 23 3 5 4 13 92539 3 3 4 E 3 8 41 3 2128 21 98 248 408 eee 200028 1 1 9 16 wae ease 2 21 s Ech so RE RAGO eee ee ee eee ee ee ee ee ee ee ee RES PRG ERGRRREES 3 1 31
20. Structure from the STRAP Model 7 3 TA COMPUTE 6x6 cis ete dahon teen bdo ented E ew deo tee eh 9d i tient eee wes 7 4 7 5 General arrangement drawing 200 c eee es 7 4 24E 0 022110 727 7 710 7707 107 21 AAE 7 7 8 Concrete Design zoe rrREEEEFEEEFERBCERRESEEECEERREETREREREREREEERENESSSESS 8 1 Ol GENGA eaer E E A EE 8 1 02 SCGUONS saroyi tske arr s E E EE G E A C ms 8 2 8 3 SEISMIC GESIGN saana aaa a adi D ia A seen 066 9 26 Jn 66 eee eed A eee eae 8 2 8 3 1 DOGS EET ESTE ae bee hee E ESE ET TTET E LOTET T T rere ee 8 3 8 3 2 COMMAS PP 8 3 8 3 3 WANG T O EEPEERERPTTCPEPMERERR 8 4 04 Design PIOGGUHEG suc uc oio EE cage Sa cee bees kee eee Cae Oe DS ade eee n EL RC C ees ante 8 5 8 4 1 INCH SCISINIC 44 ines d oa oan che TI ee a TT I oe E NN 8 5 8 4 2 Design procedure seismic 1 eee eee eee eens 8 6 69 Draw COMIN S vo ew eer occa a ctw tho aren ete eee ete ae ere noe kee ee ee ee eee 8 7 o0 DWlaW Slabs cctteceweut he ctenceSedeenre tes teebeetesnc glee secchoectascehecae 8 8 9 Brage POSIDIOGCSSO 66606600 466 OS SDE OER OT ER OT EEE OER ORES 9 1 91 INtOGUCHON 2 565 tence eee antec ne aes tatecaweteewcaeawed eeaes codes een cet ueews tec 9 1 9 2 Solution Method and Program Assumptions es 9 1 9 3 Howto use the Bridge Module 00 0 c cee es 9 2 TOPOS LIEN 2rRRyRRRRRRRRRRRRERRRERRERRRRRRERRRRRRRRRERERRRRRRFRERRREES 10 1 10 1 GENET
21. The moments are per unit width i e MX 50 indicates 50 t m m KN m m ft kip ft etc The following are the positive element results sign conventions 23 E dl My Fx tFy ro stress on z face x3 8y I stress SU 78 Mix on z face n ly x1 v 2x stress on 2 face im sx stress on z face l l 4 Fx b positive sign convention moments x A a positive sign conventions forces and stresses Mx c 0 Nue c Pd Fy Referring to Figure a above approximately equal and opposite forces act on opposite faces of the element The sign of the displayed results are for the face in the positive direction of the result axis Therefore e if FX is positive the element is in tension in the direction of X e if SX is positive the top face is in tension elc Note e for graphic results the program may modify the sign of the results in order to ensure consistency etc 5 4 2 Beams Axial force Moments and Shears Display axial force shear force and moment values at both ends of beams and either the maximum value in the span or at specified intervals lt 4o or o of the span All results are relative to the beam local axes Version 12 5 5 10 12 06 STRAP Example BEAM CONE MODE AXIAL Wo v3 MT MZ M3 4 5 O 076 1550 o 000 0 000 0 000 0 135 H 00rb 2 450 0 000 DO Ort D Or 1 833 F 5 0084 0 765 0 000 0 000 0 000 0 325 E 0 0849 1
22. a file name The default extension is RTF Note e acompany logo may be printed at the top of every page Refer to 1 4 3 Setup Print parameters 1 9 9 Print drawing Use this option to print the current display directly to the printer or to a file The printed display will be enclosed in a frame and will include a header 1 9 9 1 Regular drawing PRINT DRAWING l OK Send output to asa EET E it Seriel Setup Click the E X button to start printing Text size P mm Left margin mm Drawing size scale 1 Drawing will fit an one page Select the output unit e g printer plotter etc The devices must be installed by the Printers option in the Windows Control panel Note Use nf paper width Graphic output to create a DXF file select l MetaFiles WMF format or Enhanced Meta Use 6 of paper height files EMF format in this option then select Convert Metafile to DXF in the Files option of the STRAP main menu e Tabular output to create a delimited file Print now data items separated by a delimiter character and not by spaces suitable for Print to file import by most spreadsheet programs C Save for Print Edit drawing option select Delimited file in this option To specify the delimiter character refer to 1 4 2 Cancel i Setup Miscellaneous Fit frame to drawing Print options Setup Specify general information for the output device selected paper size graphic
23. are equally spaced along an arc Refer e to 2 1 2 fata line Define a series of nodes all lying on a straight line with varying spacing between them When 4ne defining the nodes using a cylindrical coordinate system the nodes are located along an arc Refer to 2 1 3 Define a parallelogram grid of nodes Define a base line and a height line of nodes similar to the previous two options by specifying the location of three corner nodes When defining nodes using a cylindrical coordinate system this command creates a series of parallel arcs or concentric arcs iz pg Define a series of nodes using an equation e g parabola sphere etc The equation may be one eona supplied with the program or may be user defined The option may also generate beams and or elements A i Move an existing node to a new location Hove Delete an existing node Assign a new node number to an existing node Select a coordinate system for node definition e aCartesian plane either one of the global planes or any arbitrary plane in space e a Cylindrical coordinate system Refer to 2 1 4 2 d p Search for locations where more than one node has been defined and delete all nodes except one unify a ea i thereby unifying the model at those locations 2 1 1 Single Node Create a single node at any location in the model The standard node definition dialog box is displayed Made no x1 3 E x2 0 5 AX3 OK Screen dX
24. base line The program copies the base line to every level on the height line generating nodes and connecting them with elements If the base line is a semi circle and the height line is a perpendicular line the program will generate a half cylinder if the second base line is a semi circle with a smaller radius the surface will be conical This option can also generate plane grids A powerful command for automatic element generation Generate a grid of nodes along with the corresponding grid of elements The grid outline is defined by specifying a contour and the size of the generated elements is determined by user defined parameters Delete elements already defined Renumber elements already defined Define section properties including material and assign them to finite elements JENE E Revise the direction of the local x3 axis This option is used to reverse the direction of the local x3 axis as set by default by the program az x m A L to define the edges of bending elements as pinned wm n oy define offsets perpendicular to the element liec a ul Version 12 5 2 13 12 06 STRAP The following options are available when a stage other than Whole model is the current stage Define select construction stages Different properties may be defined for each stage and beams elements may be removed New beams cannot be defined when a stage other than Whole model is active Remove an element from the c
25. define a new path by clicking the e icon Create New Folder in the standard Windows Select a directory dialog box Note the last five directories selected in this option are displayed at the bottom of the File menu and may be selected by clicking on them do not select a Read only directory Version 12 5 1 3 5 12 06 STRAP 1 3 4 Copy to a ZIP file Model files may be condensed to a single ZIP format file and may be imported back into the model list from a ZIP file To copy to a ZIP file e enter the name of a new ZIP file or select an existing one specify which of the data files to condense Title Floor Plan with elements base Iv Geometry file M Steel postp files Meighttile i Loadings files Concrete postp files Dynamic results Stiffnessamatrx P Brndge lanes data mime history M Results files Bridge Hesult files cance foran existing ZIP file select one of the following options CAIUNK dz zz zip A file with this name already exists Do you want to Add the model to the file C Replace the file C Select another IP file name Cancel where i Add the model the selected models are added to the file Replace the file the exiting file is erased and a new one is created with the selected models Select another ZIP file name Cancel the option and enter a different file name before continuing 1 3 5 UnZIP a model Models may be retrieved from ZIP files
26. design with a default dimension that may be revised by the user Version 12 5 11 2 12 06 STRAP I2 Section generator CROSEC 12 1 Program Specifications CROSEC is a program that calculates the properties of geometric sections area moment of inertia center of gravity etc The program can calculate all properties that are required for the design of cold formed light gauge sections All line sections with any arbitrary shape defined in this program may be transferred to the STRAP steel postprocessor and can be calculated as cold formed sections Two general types of sections may be defined Line sections Sections composed of a series of connected lines each with a specified thickness For example LO Define 5 segments thickness and bend radius ta create the section ans Segments may be defined in any direction diagonal Several separate sections may be defined to form a section the additional sections are called subsections Each subsection may have a different thickness and bend radius The properties of a Line section may be copied to STRAP geometry Tables of cold formed sections may be added to the STRAP property tables the user first defines the dimensionless general shape and then enters the dimensions for each segment of every section in the table Different segments may be defined as equal only one of the dimensions must be entered Properties calculated include Shear center warping c
27. directions In all cases the total load applied is the pressure multiplied by the surface area of the element Version 12 5 3 2 12 06 STRAP 3 4 Support displacement Support displacements may be entered in the direction of any degree of freedom including rotation Note that the nodes must be restrained in the same degrees of freedom as the defined d displacements 3 5 Combine loads Use this option to combine existing loading cases to create a new load case the existing load cases may be multiplied by a factor Note that the STRAP result module also has an option for combining load cases In general it is more convenient to define combinations after the solution rather than at this stage because e the solution time is decreased combinations may be revised without solving the model again since the P Delta effect is non linear the rules of superposition do not apply Therefore load combinations for models with P Delta must be defined here in LOADS rather than in the results module This option may also be used to insert an existing loading case into a new loading case 3 6 Global loads Load locations may be defined relative to the global coordinate system The program locates the nodes and elements surrounding the global loads and converts the loads to equivalent joint loads or element loads as requested by the user This option is useful in models characterized by load patterns which do not coincide exactly with t
28. e the line widths are defined in millimeters aline defined with zero width will be drawn with a width of one dot e g for a printer resolution of 300 dpi the line width will be 1 300 inch e geometry line widths also apply to the geometry for loads and results 1 4 4 Toolbars Icon bars are displayed above the graphic display during geometry and load definition Clicking an icon on the bar operates the option that it represents directly For example Use this option to customize the icon bars Up to 10 different icon bars may be defined 7 default bars are present when the program is installed The program automatically displays icon bar no 1 on the screen Clicking the icons at the end of the bar displays the following previous bars Version 12 5 1 4 3 12 06 STRAP Blank page Version 12 5 1 4 4 12 06 STRAP 1 5 Utilities The following utility modules are available Footing design Create edit a Steel sections table Note that you can add options to this menu This is convenient if you HUpie sesiel prageries want to run a STRAP batch operation according to the STBatch utility but Combine results of 2 projects any Windows Target command can be initiated i e run any program Recreate models list Convert a 57 440 Input file to STRAP Create a STAAD Geometry Input File Create a StruC AD Neutral File Create a SDMF File The STBatch utility can be used for running STRAP in batch mode or for g
29. element selection according to property groups Selection by property type x Ho Beams elements in property group will not be selected Select propert m YES Beams elements in the property group will be selected NO Beams elements in the property group will NOT be selected Note e Dummy beams elements may be selected Select meshes Select all elements in a mesh created by the geometry Element Mesh option Move the R alongside any element in the mesh until it is highlighted by a rectangular blip m click the mouse Note that all contours of all defined meshes will be highlighted with a thick line during the selection Elements on a plane For finite elements only you may impose a further limit that the elements selected will be only those lying on a specified plane This option allows you for example to define a window around an entire model while selecting only a certain level The plane is identified by pointing to an existing element only those elements lying on the same plane as this element will be selected Version 12 5 1 9 15 12 06 STRAP 1 9 11 3 Wall selection Many options include instructions to select one or more walls Wall selection is similar to beam selection Each section between the attachment nodes specified when adding the wall to the model is considered a separate wall For example Each ofthe DU sections II The blip is between the displayed The wall nearest to the Rt is hi
30. geometry file ADD the program adds the commands in this file to the data in the existing binary geometry file GEOMnnn DAT Do not write IGNORE in this line Command Lines All commands are in the regular format Before the first line of each command type a header must be entered on a separate line The headers are JOINT COORDINATES RESTRAINTS PROPERTY NUMBER BEAM END RELEASES MEMBER INCIDENCES MATERIAL PROPERTY DEFINITION SPRINGS DUPLICATE A BLOCK UNITS force length Notes There must be a space after the e Lines beginning with are comment lines and are ignored by the program No blank lines are allowed The order is not important the commands of any type may appear in scattered groups as long as each group begins with the header M m m S a o o im If REPLACE is used the program does not read the binary geometry file and hence does not know what the model is plane or space It assumes that the model is space and expects three coordinates in every node definition command Type the command COORD 2 on a separate line after JOINT COORDINATES if the following commands contain only two coordinates If the program discovers a format error in a command when reading the geometry file it exits and displays a message The error warning messages are written to a file ERR1 LST that may be displayed or printed Version 12 5 1 11 1 12 06 STRAP Refer also to GEOINnnn DAT a
31. lanes are divided into smaller strips but so will the solution time and the disk space required 9 2 Solution Method and Program Assumptions The program divides each lane into strips the width of each strip is equal to the width of the lane at that point while the length of the strip parallel to the axis of the lane is defined by the user at the time the lane is defined The program calculates the deflections in the entire model for a unit uniform load applied to each strip e g for a model with 500 strips the program solves 500 unit load cases At every beam end and at every 1 10 span and for every result type moment shear etc the program searches for the strips in every loaded lane where the corresponding result for the unit load on that strip has the same sign as the result being calculated The number of strips used corresponds to the load length defined The program then multiplies the results from the unit loads by the load intensity A similar method is used for elements the program calculates the results at the element centre and the corners The maximum deflection is calculated at nodes except at nodes that were defined as supports where the max min reactions are calculated When calculating maximum minimum results the program applies the loads to the strips according to the influence line results loads are applied only on the strips where the applied load gives a result with the proper sign Note that the maximum load
32. nodal bandwidth is 1025 Optimised nodal bandwidth is 46 Degree of freedom bandwidth is 294 Number of degrees of freedom 2 60 Now solving degree of freedom no 558 out of 2780 The original and optimized nodal bandwidths appear on the second line The actual degree of freedom bandwidth and the total number of degrees of freedom appear in the third line of the table The program displays the rate of progress of the solution Estimate the solution time by the rate of change of the number of degrees of freedom already solved If the model is unstable the program will display singularity messages The messages may be printed Refer to 4 3 Singularity 4 4 General problems After solving all d o fs the program will solve the load cases E STRAP loads solver ME E Abort LOAD CASE SOLUTION STAGE Computing forces for element 130 out of 161 Now solving load case no 1 Iteration no 2 Version 12 5 4 1 12 06 STRAP The iteration number appears only if non linear options P Delta unidirectional springs etc were specified The program copies a back up of the solution to the disk every few minutes refer to Setup The solution may be stopped at any stage by clicking Abort After a few seconds the program will return to the operating system The solution can later be continued from the point of the last backup as follows e start the program select the current model select Solve on the menu bar To r
33. once the model name will be highlighted click one of the options in the tab bar below the toolbar ES STRAP models list C STRAP Files Setup Utilities Dst Help cfe e Be i BI RI 3 Ap E38 9 2 al 5s B Models FR Geometry FRA Loads kid Results IH Steel flea Conci Er Bridge if Time his Tab bar options Solve current model Solve several models Solve mode shapes Version 12 5 1 2 3 12 06 STRAP kkk Blank page Version 12 5 1 2 4 12 06 STRAP 1 3 Main menu File options Geometry loads stiffness matrix results etc are stored in separate files The program automatically creates and names all of the data files for a model The user is not required to be familiar with the names and types of files available For all options the appropriate model is selected from the model list displayed If you select the option Files in the menu bar the following pull down menu is displayed New model Pririt Delete Copy to another directory Copy From another directory The File management operations should always Make a copy of a model be carried out by using the options in this section LHange current directory and never by using Windows File Manager Cony to a ZIP file programs e g Explorer or the DOS DEL m COPY etc commands Unip a model Display all model files Add a file ta model list Recover model geometry 1 cunka l l
34. postprocessor cannot solve models that include solid elements Solid elements are stress elements with actual thickness defined by the distance between end nodes The results are stresses and principal stresses at the corner nodes The elements are created from existing quadrilateral or triangular plate elements by lifting or rotating the plate element to the nodes on the opposite face The plate elements used to generate the solid elements may then be erased The generated elements may have 4 5 6 7 or 8 nodes elements generated with lift option from guad from triangle B nodes 5 nodes elements generated with rotate option axis of L2 pa b nodes T nadez 4 nodes 5 nodes from quad from triangle Note that solid element numbering is independent of beam plate element numbering Generate solid elements by lifting existing plate elements it ed Generate solid elements by rotating existing plate elements en Delete existing solid elements E renu Renumber existing solid elements mat Define the material properties for solid elements Define the material properties for solid elements single When a stage other than Whole model is the current stage elements may be removed or restored properties may be modified Version 12 5 2 17 12 06 STRAP 2 8 Wall Elements The Wall option enables the quick definition of complex walls that extend across multiple levels in
35. reinforcement is terminated at subspace boundaries optional lap into adjacent subspace each subspace can be assigned with different detailing parameters By default each level is a separate subspace and this is generally sufficient for most slabs additional user defined subspaces may be created along element boundaries at beam locations and at changes of slab thickness separate subspaces may be defined for top and bottom reinforcement For example thickness change Bottom reinforcement terminated at E slab step Beam A A m beam location B B subspaces HHA defau select LJ to specify the default parameters for the entire model reinforcement type bars or prefabricated meshes Steel type concrete type cover etc bars mesh parameters size min max diameter spacing length etc drawing parameters text size titles etc EN select LEE to revise any of the above parameters for selected subspaces Use this option to place bars at a different angle in a subspace For example Default orientation Rotated reinforcement select A to create drawings and add objects to them select a drawing and click 7 add slab reinforcement drawing bar schedules mesh schedules or mesh details e check the reinforcement arrangement and revise parameters if necessary Version 12 5 8 8 12 06 STRAP Examples Mesh drawing Bars drawing The program det
36. resolution etc Version 12 5 1 9 6 12 06 STRAP Title Text size e enter the name of a title that will be printed at the top of the drawing specify the text size in mm The size is used for beam numbers node numbers load and result values etc Margin Specify the left margin width The program will recalculate the default scale or the number of pages required whenever a new margin value is entered The value is added to the default margin for the printer page size Drawing size Specify the scale for the drawing The program initially assumes that the drawing will fit exactly on one page based on the paper size in the Setup option calculates the corresponding scale and displays it as the default scale There are two methods for changing the drawing size e specify the scale e specify the percentage of paper width height to be used Note that the program always maintains the vertical horizontal drawing ratio so it is sufficient to revise only one of the percentages If a scale larger than the default scale is specified the drawing will be automatically printed on several pages which can then be pasted together Fit frame to drawing opecify the location and size of the drawing and its frame EN EHA M Fit Fit Print options Print now To print the current drawing immediately Print to file To send the drawing to a file not required if Metafile is selected in Send output to The program
37. reverses the sign of the moments at JB Referring to 5 4 1 1 Sign Conventions beams and to the example in the following figure it is apparent that engineering negative moments at the two ends of the beam have opposite signs in the table xz hi3240 135 h32 1 333 C ee x1 JA JB X3 To ensure consistency when calculating the maximum minimum results the program reverses the sign of the moment at JB Therefore the moment results for the beam in the above Figure are displayed as Version 12 5 5 11 12 06 STRAP BM COMB NODE hss 2 1 43 X 1 0 00 FR 0 45 7 50 T 22 20 00 Mote the sign l reversal in the MAS 22 n z20 00 MAS table COME MIN uus uu T 5l COMB 5 4 3 Span Deflections Display the maximum span deflection The deflection is relative to the final location of the nodes not the joint coordinates For example A BEAM SPAN DEFLECTION for combination 1 Iof Exit Goto For beam 6 Beam xe x3 E p 0 000057 0 000001 b 0 10 7460 0 000001 g 0 050046 0 000000 40 0 000050 0 000000 5 4 4 Element results Element Moments forces stresses e Stresses SX stress in element result X direction on the Z surface SY stress in element result Y direction on the Z surface SXY shear stress on Z surface e Forces moments stress resultants in the result coordinate system Note e the moments are per unit width i e MX 50 indicates 50 t m m KN m
38. rotated or a mirror image may be created Refer to 2 6 J copy To define general solid elements including material location and shape of the elements Note that solid the elements may have 4 5 6 7 or 8 corner nodes Refer to 2 7 f To define wall elements sections and location Refer to 2 8 Wo To create part of the current model in a temporary working area called a sub model The sub model may then be inserted in the main model Refer to 2 9 B E T Define construction stages Different properties and supports may be defined for each stage and beams elements may be removed Refer to 2 9 B Menu bar options File Edit oom Rotate Display Draw HeMove Undo Output Help e Undo Refer to 1 9 7 e All other options Refer to the extended manual Note e the options can also be accessed by clicking on the small tabs below the main icons a DA refer also to the Command Mode manual for details on defining geometry by typing in commands Version 12 5 2 1 12 06 STRAP 2 1 Nodes Define the location of each node in space by specifying its coordinates in the global coordinate system When Nodes are selected in the geometry Main Menu the program displays the following options Define one node only Refer to 2 1 1 node JE Define a series of nodes all lying on a straight line with equal spacing between them When defining line the nodes using a cylindrical coordinate system the nodes
39. temperature difference value entered when a temperature load is applied must be according to the same units Note e maximum name length 4 characters properties may be defined in exponential format e additional user defined materials may be defined in each model for that particular model only revising the program materials will not affect the material properties of existing models Miscellaneous Refer to the program Help or the full manual Rendering Refer to the program Help or the full manual 1 4 3 Print parameters Table print styles The format for STRAP tabular output may be specified by the user A series of styles may be defined using this option each style contains information on the fonts margins lines and spacing to be used when printing the table When printing tables when in any geometry loading result or postprocessor modules the user may select one of the predefined styles and the tables will be printed in the specified format Print drawing Specify the following items Top margin Tithe amp subtitle Header small text Contour legend I Bottom margin b Left margin Right margin Note e the margins are relative to the maximum print area available for your printer i e margins may be present when zero values are entered in the above menu Refer to your printer manual Define the width of lines associated with each drawing element Version 12 5 1 4 2 12 06 STRAP Note
40. the overall lightest adequate section if a member is part of an identical list the program begins the design check from the section selected for the previous member in the list If a larger section is required for the current member the program will recheck all of the previous members in the list for the new section refer to the extended manual for detailed explanations on the Code equations used by the program refer to the extended manual for a detailed explanation on the method used by the program to select steel joists American steel table only For combined forces the program may be instructed to either calculate the combined forces at 11 points along the length of the beam using the actual forces at each point and then use the worst case for design or to combine the maximum result from each type even though they may not be at the same location two options are available for the design of angles and other doubly unsymmetric sections created in the Section editor utility the program may use either the principal axis properties Iu Iv or the major minor axis properties Ix Iy For general non symmetric sections e g T sections the program by default combines the maximum stresses even if they are not at the same location on the section unless the exact flange location is specified 7 5 General arrangement drawing Create a General arrangement drawing Line diagram for any plane in the model For example I VW x27 The
41. to structure and is learned mainly from experience In general an ordered numbering pattern is recommended When numbering the model note the following points The program contains powerful commands for generating the definition of large groups of nodes and elements these commands require an orderly numbering pattern Numbering does not have to be consecutive Nodes which are not connected to the model are ignored Nodes may be located anywhere along a beam element Node numbering and element numbering are independent The structure may contain nodes 1 2 3 4 as well as elements 1 2 3 4 Ifa structure consists of both beam and area elements the same element number may not be given to an element of each type Solution time is not dependent on the numbering In all cases it is recommended that the user prepare a sketch showing all numbering before defining the model Batch Mode Similar to Command Mode except that the data is entered in a data file external to STRAP using any editor program Version 12 5 1 7 4 12 06 STRAP 1 8 Coordinate systems Coordinate reference frames are required to uniquely describe the position of a structure in space the direction of applied loads and the direction of computed reactions displacements forces etc In addition the coordinate systems are required to reference other structural information such as element properties STRAP uses Cartesian reference frames A cyli
42. to the centre of a circle is copied radially around the circle the x2 axis of all the copies of the beam will also point towards the centre of the circle e Element local axes The local coordinate systems of the copied elements are selected so that the axes of the copied elements point in the directions that are as near as possible to the directions of the axes of the original elements The block to be copied is defined by selecting a group of nodes using the standard Node Selection option only elements with all of their end nodes selected will be included in the block The location of the copied block is defined by entering the new location of reference nodes at an existing node or at any coordinate if the distance between the reference nodes is changed in the copied block then the element dimensions will be revised proportionally e the location of the new block may be defined by rotating and translating the original block e the two blocks may have a common intersection line the program automatically Unifies the two blocks so that they are connected e the program may be instructed to connect the new nodes and the corresponding original nodes with beams e the command may stretch or shrink the dimensions of the block but will always maintain the same node element layout For all options select the nodes that define the block Version 12 5 2 16 12 06 STRAP 2 7 Solid elements Define solid finite elements Note the Bridge
43. will assume that these sections are welded shapes Combined rolled sections may be defined 2L I etc The following terminology is used throughout the program Mastertable The initial complete table of steel sections British American European etc or User e Modeltable The section table for the current model containing sections from the selected master table e Section type Section classification according to shape e g CHANNEL RHS Z LIPS etc e Group A user defined list of sections which may contain sections from several types The program either selects a suitable section from a list or checks a specified section In the following cases the program will by default check the section defined in STRAP geometry ifthe section properties of the member were defined as a steel section using the Steel table option e combined sections defined in the STRAP geometry or in the Steel Postprocessor e ifthe section properties of the member were defined using the Define the section dimensions option the program will assume that the member has a Built up welded section with the same dimensions Note that only Pipe Tubes L shape and symmetric shape shape and T shape sections will be converted to Built Up sections ifa tapered section was defined in STRAP and the properties at both ends of the member were defined using the Define the section dimensions option the program will check the tapered section
44. 1 Zlax2 D Hax3 End definition X1 X2 X3 global coordinates of next node to be defined dX1 dX2 dX3 distance from previous defined node Node no number of next node to be defined MM Version 12 5 2 2 12 06 STRAP The program numbers the nodes automatically by assigning the next available number to the node being defined The user can override the program and specify the number of the next node by moving the into the Node no text box and typing in a new number Click to return the crosshair to the graphic display without leaving the current option and without creating the node beam etc End definition to abort the current option e to create a node at the coordinates currently displayed Plane model There are two methods available move the mouse so that the R is located at the correct X1 X2 coordinates as displayed in the Dialog Box adjust the Step if necessary click the mouse move the into the X1 text box in the Dialog Box Either type in the correct value or click the 5 buttons until the correct value is displayed Repeat for X2 and press to complete the definition Note that if you click and hold the left mouse button until the is in the Dialog box then the initial coordinates in the box will be at the location when the mouse was clicked A node numbered with the Node no is created and displayed Space model The X3 coordinate must be defined in the Dialog box mov
45. 1 5 4 Combine results of 2 projects Tables may be written to ASCII files in user specified format using the STBatch utility e he following terminology is used throughout the output modules Load cases defined in Loads prior to solving the model Note that Load CASES some of these cases may be in fact Combined load cases but are still referred to as CASES Combinations of load cases defined after solving the model using HOS KAAMERA een the Combinations option Version 12 5 5 1 12 06 STRAP 2 Combinations Use this option to define combinations of the load cases for the following output modules e tabular results graphical results design postprocessors Note 5 1 For a detailed explanation of Groups and Library refer to 5 1 1 Combinations General the rules of superposition do not apply for non linear elements Therefore load combinations for models with tension compression only elements unidirectional springs etc must be defined in loading Combine ld and not after the solution using this option 1 Combinations General Each Combination is defined as a combination of load cases each of which may be multiplied by a factor Combinations may also be retrieved from a Combination Library combinations defined for the current model may be added to the combination library for use in other models Groups of load cases may also be defined If a group is added to a combination defi
46. 1 OL 2 1 2041 2L 1 A 2 0 7 5 D L n n 321 20 1 2L 1 AM 320 7 5 D4 L VV 4 1 0047 dv 4 0 75DA 5 1 00 1 dy 5 0 7 50D After the geometry and loads were defined in STRAP and the model was solved the following data was defined using the Steel design module options Identical aupparts combined Version 12 5 7 7 12 06 STRAP Section Limit selection to Code BS5950 Eurocode 3 1 AISC Beams Diag Bracing EQ D ANGLE neni mam 5E Same section Column 8 9 10 specified as an identical group Column 11 12 13 30 31 specified as an identical group Column 15 16 32 33 specified as an identical group Bracing 20 and 22 specified as an identical group Haunch beams 25 and 26 specified as an identical group Supports Members 4 5 6 Continuous support for z major axis bending major and minor axis buckling The support is provided by the floor slab The continuous buckling support for both axes cancels the axial force check Member 16 Minor axis buckling support at mid span The support is provided by the beam perpendicular to the plane of the frame Member 18 Support at midspan for z major axis bending major and minor axis buckling The support is provided by the walkway passing over the beam This support may be defined using the option Define supports at concentrated load points Members 20 22 Support at the midspan of the bracing for major and minor axis bu
47. 10 ra 1 0 0 3 4 28 3 1 5 16 1 00 3 4 e 23 1 1 e EDITI e select x e double click one of the cables in the table the program superimposes the minimum maximum eccentricity range for this cable For example Hearn to Allowable eccentricity range for selected cables centre of mt oo gravity of beam Heam hattam Beam Heam start end the cables may be defined with a straight or parabolic trajectory select one of the options and define the trajectory interactively on the screen click when finished cibis select 9 0 again and choose another cable The allowable eccentricity range displayed will again be only for the selected i e it will reflect the prestressing and eccentricity of all other cables with defined geometry Placing this cable within the range insures that the total force eccentricity of all cables provides a satisfactory solution Version 12 5 12 06 STRAP 10 4 Magnel diagrams The prestress force P and the eccentricity of the force e must be selected by the user any number of combinations of P and e provide an acceptable solution The stresses at the extreme fibres are limited to the Code values and are checked at every stage for maximum and minimum moments with the actual prestressing force after losses This gives four limiting stress conditions e minimum moment top fibre e minimum moment bottom fibre e maximum moment top fibre e maximum moment botto
48. 2 12 06 STRAP Self 1 if BEAM list AJ Ad The words in capital letters are keywords which must be entered exactly as they appear in the format statement The program normally requires only the first one or two letters of a keyword in order to identify it Underlined letters indicate the letters that the program reads Simplify the input by typing these letters only For example S instead of SELF B instead of BEAM Lower case letters indicate numerical data In general parameters beginning with i j k l m n indicate integer values and all other letters indicate decimal values examples n n1 are symbols for node numbers integers p p1 are symbols for section dimensions decimals Decimal values may also be entered exponentially For example e 510 may beenteredas 5 1E2 or 5 1E 2 e 0 0037 may be entered as 37E 2 or 3 7E 3 Do not leave any blank spaces between the numbers and the letter E Parameters in brackets indicate optional input In the self weight example above f may be omitted Keywords in brackets indicate a choice of one of the keywords listed In the above example type one of X1 X2 X3 to specify the direction the loads act ist indicates a list of nodes or elements in the List Format For example 1 9 17 20 1 3 TO 6 12 15 18 TO 30 3 TO 11 BY 2 20 TO 24 34 The last example is equivalent to entering 3579 11 20 21 22 23 24 34 A list can consist of up to 50 items where 1 TO 6 is one it
49. 6 5 3 1 Results at Element Centres 0 0 0 0 ee ees 5 6 5 3 2 Result Contour Map 0 0 eee eee eee eens 5 6 9 9 9 Results along a line 4 PT T 5 7 5 3 4 Deflections isreriresorrirs fri brrE AK Er Rss 5 8 54 TabularleSunsS eua cone usa v1 971 9 3 9 9 26 8 2 E E 19 0 R E 00 o Nee eee eee es 5 8 5 4 1 Tables Sign Conventions 0 cee eee nr 5 8 5 4 1 1 Sign Conventions BEAMS isses 5 8 5 4 1 2Sign Conventions Quadrilateral and Triangular Elements 000 ete eee 5 9 5 4 2 Beams Axial force Moments and Shears a 5 10 5 4 3 Spal DEHeCHONS 3 xe eens cu ah cece Bees ee a eee Re Gen a ete See 5 12 5 4 4 FP SIE TOSS aca eae pede ah cathe ca i rit tard d Edd pq a d ad sgh ae cede dst Unda 5 12 5 4 5 scc dq e PRTLC 5 13 Version 12 5 vii 12 06 STRAP 6 DVMANNG ANAIVSIS rrtt 88 6K ECE EECEED FESS EECECE RECO EECSEE CEES FOES EES 6 1 6 1 Mode Shape and Natural Frequency Analysis 000 cece eee es 6 1 62 Seismic AnalysSliS a circ tac ew domm de bala ed Ate eae ae desl ace ec ale S ee ae ae oe ee 6 1 6 3 Forced Vibrations and Time History Response 00 cee e eee eee es 6 3 7 Structural Steel Design ceca eek eee eek eek eee eke eee renee eee Re dene d 7 1 7 1 Steel Design General 0 00 es 7 1 7 2 Steel section tables and selection 0c cece ees 7 2 7 3 Creating a Steel
50. 9 9 chan Red dE Rc dae eens eee eee ea ee ae es 1 5 2 1 5 7 Create a STAAD geometry input file 2 0 0 0 cee 1 5 2 1 5 8 Create steel detailing files llle 1 5 2 HO OXF ODHOlS 245 xus dou ee Rd X ad D bd pu sid wean ete Geneon d indiquer bare 1 6 1 1 6 1 Convert metafile to DXF 0 0 ans 1 6 1 1 6 2 Convert STRAP file to DXF DXF export 0 0 0c cee 1 6 1 1 6 3 Create a new model from DXF file DXF Import 0 0 0 0 ccc eee eee 1 6 1 1 7 Getting Started 21 2402c2022040 ndn om lie Hc DC ORA D nt iH m C ene 1 7 1 1 7 1 Selection of the Computer Model 0 0 0 0 eee res 1 7 1 1 7 2 Inputting the Model 0 0c ee RR IRR Yrs 1 7 4 Version 12 5 V 12 06 STRAP 1 8 COOrCINAlG SVSICIMNGS ood eck seh ae once D eee sek eee eee ee eee ees 1 8 1 1 8 1 Global Coordinate System 0 0 0 ee ee en ee eee eee 1 8 2 1 8 2 Local Coordinate System 0 0 nanana anana ee ee eee tees 1 8 2 1 8 2 1 Beam Elements eee ne eens 1 8 2 1 8 2 2Quadrilateral Finite Elements 222i eee 1 8 4 1 8 2 3 Triangular Finite Elements 22i ehh hh hh hh 1 8 5 1 8 2 4Wall elements 0 0 tet tes 1 8 6 1 8 3 Sign Conventions Forces and Moments 00 cc eee ee eee eee ees 1 8 6 L9 General oDllOllS 2icceceec ace wteecere cise E et ee whew ete UST EIE IE EN 1 9 1 1 9 1 SGD cba cu Peas ee Sew oman aa aa hah eae eee ee Oe ee Bae bee 1 9 1 1 9 2 Dialog DOX
51. AP 8 5 Draw columns Detail the reinforcement in computed columns and create drawings showing elevations and sections laplengths no of links etc are determined according to the relevant Code clauses e the detailing may be drafted according to either of two options drawing the sections and elevations are arranged on an engineering drawing table the sections and elevations are arranged in tabular form For example LevelCol H 4 10 r So I IL ILIL IIITIEILIIIELIEBIHIBBEBIIEB E 1 55 30 O 40204201 3 5 6 PESO 4020 2015 5 6 Note that the default parameters for the drawing table are assigned to the column when the columns are created the parameters can be subsequently revised only by using the Drawing parameters option in the side menu Creating the column again will restore the default parameters Bar schedule e Drawings The schedule is added to the drawing and includes all the reinforcement currently displayed Tables The schedule is created in a separate file and may be viewed edited and printed using the BARSW program Version 12 5 8 7 12 06 STRAP 8 6 Draw slabs The program calculates and details the slab reinforcement either as an arrangement of individual bars a pattern of prefabricated meshes or a combination of both To calculate detail and draw slab reinforcement pad select efine to define subspaces Subspaces are defined areas on a slab
52. ES je ere dee ace d d a qa ee ol ed ey Be ee dee 1 9 1 1 9 3 SNOG MENUS caacartsoueepondee qe pane aren auras ome cornea aod eponeeG aes bea 1 9 3 1 9 4 Side MENS v3 90 30r 30 378 dris o cade Ba eee See a ee eh he eee ee ae He 1 9 4 1 9 5 FCW antigo E sess ada ee wa cued neem ene d 35 9 qd p t cau ae RE di 1 9 4 1 9 6 ICOM Dak siege e ban meony onan beaeeereceae Game tees Gane oy onan seas a eee seas os 1 9 5 1 9 7 JOG sips ear eat Reh oe Sees ee hoe E ear Gee aes a ae eee Ge ee ee we 1 9 5 1 9 8 FUG CGS E Qe ae e ew eno dd ew ee ae rw aed Honey peed ee ee ere 1 9 6 1 9 9 xii PPFTTT 1 9 6 EIS Erie A S 1 9 6 1 9 9 2RHendered drawing 0 ee ases 1 9 8 1 9 10 Prinvedit drawing s duos iom ctm 9x8 ond 3 Re e ea ox e oes DR See legs 1 9 8 Ie Entities SOIBCHOE dede 9120252099 2 m F9 p3u SE PSEUYTIJPLespQeeT I4 oder PEE 1 9 10 Vitel INOOG SSlCCHOM ouv ex de dep boo veg viva vr PN ed eb oe bee ded eie eis 1 9 10 LOS Beam EMA Oa C cra dci Wr ae ge IDR Ia UU RIDE a draco i IN OU eI I RC PURO dA 1 9 13 1 10 Command mode ss 2 dc rae e UC CE VO CR C D RC AC RC RC C eu ar cg a 1 10 1 1 10 4 Enter a Command sse rr 1 10 1 1 10 2 Revise a Command see rs 1 10 1 1 10 3 Retrieve a command from the Clipboard 0 eee 1 10 1 1 10 4 Command Format General leer 1 10 3 1 11 Batch mniode au uaupanhus QcitaE S E eo Sao SH REOR B ORE IE BO
53. How to use FOUND FOUND can be run either as a standalone program or can be run from the STRAP result module to design the footings at supports in STRAP models 11 2 1 Stand alone program e Specify column dimensions and design parameters Select Design in the menu bar and then Parameters in the pull down menu Define loads Select Design in the menu bar and then Loads in the pull down menu more than one load case may be defined The program will now display a solution based on the specified parameters loads and dimensions e Refine the footing base dimensions Select Design in the menu bar and then Dimensions in the pull down menu enter new footing base dimensions eccentric footings may be defined at this stage and the program will check their validity Each set of dimensions is displayed in the table on a separate line click on any line to select a solution Refine the footing height dimensions Select Design in the menu bar and then Sloped footing in the pull down menu enter a new footing height define a different exterior height to create a sloped footing and the program will check their validity click on any line to select a solution Print results Select Output in the Menu bar and the Print drawing or the Print results options 11 2 2 STRAP post processor The program designs rectangular spread footings at all nodes assigned with restraints and springs if specified by the user The postprocessor automatically r
54. Local axis points the moment is determined by the out af screen following right hand rule e Positive moment iz Right hand COUHTER CLOCKWISE Examples Loads Joint loads are always defined relative to the global coordinate system Beam loads may be defined relative to either the global coordinate system or to the beam local coordinate system x1 Local M The load iz Az Fositive if referenced to the FAZ Global X1 axis d Negative if referenced to the Local xz axis Mx2 AS 2 F1 M wd Global MX3 KT FA a Joint Loads b Beam Loads Version 12 5 1 8 6 12 06 STRAP Beam Results Tabular Moment shear and axial force results for beam elements are always displayed relative to the beam local coordinate system The sign conventions are xz i v2 v2 T Lm ge S L JB Dim iy i bee ei 7 n T xo Finite Element Results Tabular Moments forces and stresses for finite elements are displayed relative to the element local coordinate system Forces and stresses are positive if acting in the positive direction of the parallel local axis Referring to the equations in 5 4 1 2 Element results sign conventions a positive moment creates tension on the x3 surface of the element E r cie M Note that STRAP s graphic postprocessors will often unify and reverse the signs to display the results according to accepted engineering sign conventions Refer to 5 3 Element result types for
55. RES T1 No walls in the wall group will NOT be selected OK Cancel Version 12 5 1 9 16 12 06 STRAP 1 10 Command mode The following section explains in general how to define the model using the Command Mode For a complete explanation refer to the Command Mode Manual The commands are typed in by the user in the Command Mode Box at the bottom of the screen the program automatically updates the graphic display of the model It is important to note the following e the Graphic Mode and the Command Mode may be used concurrently every time a part of the model is defined in the Graphic Mode the program automatically writes the equivalent command in the Graphic Mode Box Therefore the Command Mode Box contains a complete record of all that was defined in the current session 1 10 1 Enter a Command When you enter a definition type the program automatically writes a header in the Command Mode Box For example when you select Nodes the Command Mode Box appears as f JOINT COORDINATES nm To type in a command move the gt below the last line in the box so that the I cursor appears click the mouse Type in the command in the correct format and press Enter the Graphic Display will be updated 1 10 2 Revise a Command All commands are entered in the command box as the model is defined The box displays only two rows and so the commands are scrolled up and disappear the box can be enlarged as any Windows
56. SC AASHTO AISI ACI318 CSA 16 1 A23 3 C136 Eurocode2 Eurocode 3 Eurocode 4 IS 800 18 456 GBJ17 Foundation design program Section generator program Command mode batch manual Verification manual Demo and Tutorial examples American units ft kip Demo and Tutorial examples Metric units KN meter This manual Condensed STHAP manual This manual Examples A 2 12 06
57. SS Se x Select by window select by window mm y aneel Select by polygon Select by polygon Select all beams Select meshes Select all elements Select elements with Select beams with C One node in the window polygon Both nodes in the window polygon C One node in the window polygon All nodes in the window polygon Select only beams parallel to a beam C Multiple selection Select only elements in a selected plane I Limit selection by property Select only elements parallel to one Multiple selection Limit selection by property Individual elements Select a single element only by moving the r alongside the element until it is highlighted by a rectangular blip m click the mouse The number of the highlighted beam is always displayed at the left hand side of the Dialog box Beam 3 TO aM Cancel End selection You may also type in the number of the beam to be selected in the form of a list When all the beams have been selected press or click the mouse without moving the s In space models more than one element may be at the same screen location only the coordinate perpendicular to the screen is not identical In such a case the program will display a list of elements at that location and request the user to select one Select one of the following beams which are at the same screen location Beam 48 JA JB 3 Keam 61 J 29 JB 30 Highlight the line with th
58. The following load types may be defined Uniform load Specify the uniform lane load units are t m kip ft etc not load area the maximum length of the sum of the loaded strip widths and the load length reduction factor table Vehicle load Select a vehicle load or vehicle group from the list box define a factor to increase decrease the load and the direction of travel most vehicle loads are not symmetric Note that the program can check both directions and use the worst Knife edge load also used to define concentrated loads Define load cases Load cases are defined by assigning lane loads to specific lanes Set load case in side menu and click the Define icon assign the defined lane load to the defined lanes define permutations the program will create additional load cases by interchanging the lanes the lane loads are assigned to Note that load cases may be deactivated activated Display a specific result for any node beam element or specific point The results are the value of the maximum minimum result and the corresponding loaded strips location of vehicle loads and location of knife edge loads select Results in the menu bar select Draw applied loads for selected result in the pull down menu Specify max or min select result type specify location Transfer results to STRAP The program appends transfer load cases to the STRAP result files Maximum or minimum results may be selected
59. URE LOAD COMBINATIONS GLOBAL LOADS end of load case END end of file END STATIC Notes n all command lines there must be a space after the No blank lines are allowed e The order is not important the commands of any type may appear in scattered groups as long as each group begins with the header Thelast loading case should not have a END command prior to the END STATIC command Example For the following space frame example the STATnnn DAT file is x2 ASCII SELF WEIGHT AND ROOF LOADS Vertical load BEAM LOADS 2 0 tim on all beams SELF X3 B 2 TO 16 U GLOB FX3 2 0 B 2 TO 6 END WIND LOADS JOINT LOADS FX1 5 0 N 6 END STATIC Version 12 5 1 11 3 12 06 STRAP 1 11 3 Batch mode Combinations A file containing load combination commands can be imported into STRAP by cutting and pasting the commands in the Results Define revise combinations option e type the combination commands in a Windows editor program such as Wordpad in the format TITLE tit optional Ic1 f1 Ic2 f2 Icn fn G1 fg1 Gn fgn where tit combination title string The program will create a default title if this line is omitted Icn load case number fn factor for load case n fgn factor for group n Example for a combination 1 4 load case 1 1 6 load case 3 1 2 group 2 titled Dead Live Group 2 type TITLE Dead Live amp Group 2 11 4 3 1 6 G2 1 2
60. Version 12 5 9 2 12 06 STRAP For the same transfer load case select either maximum minimum value for each result type maximum minimum for a specific result tyoe and corresponding results from same calculated load case Note that the transfer for very large models with many lanes strips and calculated load cases may require several hours the progress is displayed on the screen Version 12 5 9 3 12 06 STRAP Blank page Version 12 5 9 4 12 06 STRAP I0 POSTTEN 10 1 General POSTTEN is a STRAP postprocessor program that designs post tensioned beams and slabs in solved STRAP models The design may be carried out according to various design codes The STHAP model must either be a plane frame or a space frame grids will not be accepted by the program axial forces from prestressing cannot be added to load cases The program uses the following terminology e strand the basic prestressing unit a single wire or a group of wires e cable a group of strands For example strand E S inthis example Iu Quo euo the cable is defined with 3 strands con Qoo ooo oo oO eo the strands are the 7 wire type Cable The following STRAP beam sections are accepted by the program e all sections defined by Dimensions except round sections All sections defined by Properties A I etc The program creates an equivalent rectangular section all solid sections defined in CROSEC and imported i
61. WONUIOCAGS lt ip cr ve cee dtr udsa en E du EXE EUER ER X P dca EGER E dees deed RC EC dE 3 2 DPHMEI INDICI IMP 3 2 oo Blementio8dS 25 5509 5 PEE CREDE EEUU EE ME ee eee ee du d eee cae paci 3 2 3 4 Support displacement eereeeeeeeeee enhn 3 3 3 5 Combine loadS aser wu gari Hb 10 F0 809 8196 8 9 eee ee MAR op 0709 NI RS DUE ANH 3 3 45 GlobaldOdUS uox de weet 95 2 242929 3 99 293 999 2 E Sex d eee eee coe dod a 3 3 37 Solid J680S x xcu Rai dac o 26 NCC d t ACRI UN DD o CC 0 6 Owe ue ew ee a C RN owe 6 3 3 389 WIDndIOOUS Gesausre we tosqu bau eda d Rad cone eee eee P Wa cau Papa edd d dard sa dea een 3 3 4 Solve the model eeeeeeeeh hh nn 4 1 4 1 Solve general MPEEEEETRSIITOEITIOTTITILODOIT TOO OT D TITTTTTTTTTETTIEUETDEMT 4 1 4 2 Solution method m 4 2 45 SINQUIQUIIY Prc rmT 4 3 4 4 Problems General 00 0 cece eee eens 4 4 B ROSUNG wd EE RO ERO RE ROC ee eee ee ese eee eee eee RN 5 1 51 GOMDMANONS uses vios uds Nae q qid aieo A cheno vaL 19 bar an CoL a de pL owe we 5 2 5 1 1 Combinations General 0 0 00 e rr 5 2 5 2 Element Coordinate Systems cceeeeeeee eene 5 3 5 2 1 Result Coordinate System X Y Z caseus suam waa dy anke dox Rs Cd 5 3 5 2 2 Reinforcement coordinate system 0 eee ns 5 5 5 3 Graphie LI C ects wrest EAE soe EO dee weed one 5
62. aa a 2995 941029 E E beets wave od d eee 10 1 10 2 How to use the program ereeeereeerr nnn 10 1 10 3 How to define cables ehem nitri ed wondered mue om did uda eee ub hee eid 10 3 10 4 Magnel diagrams x aiio iari e RR OUR ha ee Rus oa Rm ee wee 9 1 3 er ee a a eee 10 4 11Foundation Design xu ssim urna 9HEh ra RREHEHECRI CERE REA EECEE SEE ESI AE ISAEA 11 1 11 1 Program Specifications leeeeeleeeeeeee ern 11 1 11 2 How to USE FOUND 52 ux acing c cipe cam acr a ea ine eae ney eee hia i 11 2 1123 Stand alone program uae anie coded om m Med Bon R9 Moe gon Ple AS Roe dle a Ew Cr 11 2 11 222 SIBAPBoSU DIOGCGSSOF 2 72 91 arae ac 6794 9179 09 98 6n rco do BC d 8 RERO in m aed 11 2 Version 12 5 Viii 12 06 STRAP 12Section generator CROSEC es 12 1 12 1 Program Specifications waa conwkws Gee maio dee RC wee Or RU riu WR d d 12 1 12 2 How to use the program ee eeeeeeeeeee hh 12 2 12 3 Hints and suggestions nre od mx dr Y eee ud eR NOE oder RR Un LR EQ d 12 2 A1 Hardware Requirements and Program Capacity A 1 Ac Prtrn ngine Manual ss lt ccccccne ccc cece cece cece cee REG ERREUR ERES A 2 Version 12 5 ix 12 06 STRAP kkk Blank page Version 12 5 X 12 06 STRAP 1 General This User s Manual provides a concise summary of the main features of the STRAP structural analysis and design pr
63. actual reinforcement area may be modified by the user but not less than the design forces e column longitudinal reinforcement is calculated from the design forces but may be increased to ensure that the sum of the column moment capacities at a joint exceeds the sum of the beam moment capacities ZMc XMb gt k e column shear reinforcement is calculated from shear forces derived from the moment capacity of the beams connected to the ends of the columns but not less than the design forces Note that beams must be computed prior to columns as the column capacity is dependent on the end moment capacities of the connecting beams The design procedure is as follows Beams T comp Compute the beams select Ue e Check results revise parameters properties etc if necessary and compute again HH 7 defau eti e Specify the exact increased reinforcement at all beam ends top and bottom select its Jor LE and click the Mady Reint tab To check click Data tables and select Display reinforcement table e Display the reinforcement areas and the corresponding moment and shear capacities click Data tables and select Display seismic capacity table Columns T comp Compute columns select E e To display data used to calculate links stirrups click Data tables and select Display column shear table Check results revise parameters properties etc if necessary and compute again Version 12 5 8 6 12 06 STR
64. ails the reinforcement as follows As req d is calculated at the center and four corners of each element the maximum of these values is used for the entire element Bars or meshes are selected according to the parameters The program arranges the reinforcement in two patterns each with the longer bars in a different direction and selects the pattern with the smaller weight of steel Hints and Suggestions for the Bars option If you decided to place bars only where required but the program details bars over most of the slab area select Results in the toolbar and then Display detailed results note the total weight of reinforcement in the slab select Defaults or Parameters and set the option to M Put bars also where As 0 display the revised drawing and check the total weight of reinforcement again the second solution is preferable if the weight increase is relatively small because the bar arrangement is simpler and more uniform if you selected User defined bars mesh and additional bars mesh click the Edit icon and select Display only additional bars ifthe additional bars mesh have been detailed over a relatively large area decrease the spacing and or increase the diameter of the fixed bars mesh so that the additional bars are placed only over a relatively small area if there are small openings in the slab it may be more practical to detail the slab with bars placed over the opening to be cut away o
65. al beam reinforcement at the support may be increased by the user kis specified by the Code Meo 2Mc 2k Mb Version 12 5 8 3 12 06 STRAP The program ensures that the columns comply with this requirement using the following procedure e Mb is calculated at the joint e the moment is then apportioned to the columns above and below according to their relative stiffness e the resulting moment is then applied as a separate load case at the column top bottom along with the factored axial load additional reinforcement will automatically be added to the column if this requirement governs These load cases are marked as seismic in the column extended detailed results Shear Similar to beams the seismic design shear forces Ve are calculated from the probable moment strengths of the beams framing into the columns The sum of the beam moment capacities at a joint are apportioned to the columns above and below according to their stiffnesses he 4 Mlb F column stiffness 1_ MET column stiffnesses ilc 2 and Ve Mc T Mc B L Stirrups links are calculated from Ve subject to the minimum Code requirements In general closed hoops at reduced spacing are required at all locations where plastic hinges may form and to a distance x beyond At the base of the column the program calculates Mc based on the column capacity because no beams frame into the node Mc Md capacity factor fy fye where M
66. allows transfer of moments into the coupling beam elements cannot transfer moments at their corners For example Coupling beams Generated beams Note e The program creates a single element between nodes along the height axis for each segment Normally this implies a single element per story height Testing has shown that the results are sufficiently accurate for typical long multi storey walls refer to the STRAP Verification manual Cutmmy For short walls improved accuracy will be obtained if dummy nodes are defined between floor levels and long segments are defined as more than one segment Wall defined as segments Existing grid of nades 1 4 O S e The wall segments are connected to the rest of the model only at their end nodes however there may be existing nodes that lie within the segment width but are not connected to the wall The program can search for such nodes and automatically create rigid links to the nearest wall corner node Rigid links to nearest comer node Existing nodes within segment width e The results for wall elements are presented in the form of beam results one axial force moment and shear value for each generated element When a stage other than Whole model is the current stage e walls may be removed or restored properties may be modified Version 12 5 2 19 12 06 STRAP 2 9 Sub model A sub model is a model defined in a temporary working
67. ally writes IGNORE in the first line of the GEOINnnn DAT file REPLACE the program will use this file instead of the existing geometry file i e it ignores the GEONMnnn DAT file ADD the program adds the commands in this file to existing geometry in the GEOMnnn DAT file If data is defined in both files the GEOINnnn DAT data will overwrite the GEOMnnn DAT data If a format error is discovered in a command the program exits with a warning All warning and error messages are entered in a file ERR1 LST which may be displayed or printed After reading all of the command lines in the file the program changes the first line back to IGNORE Version 12 5 1 11 2 12 06 STRAP 1 11 2 Batch mode Loads There are two methods for defining STRAP loads via external files Using the Clipboard Creating a STATnnn DAT file An ASCII file containing all of the load commands for a model may be created and updated external to STRAP The file name mustbe STATnnn DAT where nnn can be verified by selecting the Display all model files option in the Files pull down menu on the main menu bar The file format is as follows 1st line ASCII for each load case 1st line load case title All loads must be in the command format as explained in detail in the Command Mode manual Before the first line of each load type a header must be entered on a separate line The headers are BEAM LOADS JOINT LOADS DISPLACEMENTS ELEMENT PRESS
68. and reinforcement calculation methods are totally different All continuous beams and columns may be manually identified by the user or automatically by the program the program uses the information from STRAP geometry for determining support locations and widths and section dimensions if possible The program then designs the beams and columns according to user specified parameters e Walls are identified automatically by the program Quad and triangular elements cannot be designed as walls The following figure shows a simple plane frame analysed in STRAP n order for the Concrete Postprocessor to design the structure beams B1 B3 and columns C1 C4 must be identified so that the program can apply all of the relevant Code clauses for continuous elements For example Beam B1 and Column C4 must be defined ignoring the dummy nodes Version 12 5 8 1 12 06 STRAP 8 2 Sections The program converts the STRAP sections into design section as follows e Steel sections sections defined by properties tapered sections tubes and pipes are considered as Undefined the program will not design beams or columns with undefined properties in any of the component spans Beams Rectangular and L sections dimensions are maintained e T and l sections major axis converted as defined minor axis converted to rectangular section with similar dimensions e U sections major axis converted to rectangular section with similar
69. ane stress element Quadrilateral Elements e Bending The program divides each rectangular element into four HSM triangular elements by creating a new node at the element centre The program then uses matrix condensation to delete the new node e Plane Stresses The program uses a linear strain plane stress element 4 3 Singularity The program may also display additional messages during the solution phase indicating that it encountered problems in solving the equation i e the stiffness matrix was found to be singular Singularity warnings may be printed Singularity indicates that the matrix determinant equals zero The cause of singularity is instability of the model ALWAYS DETERMINE the REASON for SINGULARITY There are two types of singularity Local Singularity The model as a whole is stable but there is local singularity at a node zero stiffness at node in dof dof was restrained The program will restrain the DOF and proceed with the solution Several examples are Plane truss XS was not restrained at all nodes e Planeframe All beams connected to a node are pinned e SOSpace rame Torsional moment of inertia J not defined Note In many cases of local singularity the corrective action taken by the program will lead to the correct solution e g plane truss example above However the solution time required will be greater otructural Singularity The entire model is unstable The following message appear
70. are defined relative to the global coordinate system or to any arbitrary local system defined by three nodes The positive force and moment sign conventions are direction af Fad positive moment TE MXZ Ae FA p hx T 1 positive hx direction ae of axis 47 Right hand 3 2 Beam loads Beam loads are uniform linearly distributed or concentrated loads applied anywhere along the length of the beam between the end nodes Self weight and temperature expansion contraction or gradient are defined as Beam Loads Beam loads may be defined either in a direction parallel to one of the global coordinate axes or parallel to one of the local coordinate axes of the beam Local the load is parallel to the beam local axis specified Global the load is parallel to the global axis specified and is applied to the total beam length Global projected the load is parallel to the global axis specified but is applied to the projected beam length as projected onto the specified global axis uniform and linear loads only The following figure illustrates the Global Global projected and Local beam loads commands d i L X GLOBAL A3 GLOBAL PROJECTED x LOCAL Beam local xz axes 3 3 Element loads Element pressures are applied to the entire surface area of quadrilateral or triangular elements The pressure is not necessarily applied normal to the element surface the load can be applied in any of the local or global axis
71. area The model may then be copied to the current model any number of times at any location and at any angle Note that the entire sub model geometry may be copied to the main model including supports springs offsets rigid links etc The sub model may also be saved as a separate model in any directory There are three methods for creating the sub model Submodel Select how to create the sub model Existing model New definition Cancel Note that the main model and the sub model are open simultaneously until the sub model is closed the user may jump back and forth at any time by clicking the icons The following options are available Models Wizard Create the sub model from one of the models in the Wizard library Note that the sub model generated by the Wizard may be revised before it is added to the current model Existing model Retrieve an existing model from any working directory Note that the sub model may be revised before it is added to the current model New definition Define a new model and add to the current model Note e the program will not create a new node at the location of an existing node e supports springs at nodes in the sub model that are not copied will not be added to the main model e the program will not create a new beam element at the identical location of an existing beam element restraints or springs defined parallel to global axes in the sub model will be oriented in t
72. art and Grid lines F DXF points end nodes the new node are created at the point of intersection of the two lines More For example create the node at the centre of the bay first line 5 16 second line 6 15 Intersection by coordinates Using the e define two lines by pointing to their start and end coordinates the new node will be created at the point of intersection of the two lines Define a node at the center of a line Create a new node at the centre point of the imaginary line connecting two existing nodes select the start and end nodes of the line e Define a node perpendicular to a node line A node single node start end node of a line etc may be defined at the intersection of a line defined by two nodes and the perpendicular to the line from a third node Offset from a node and perpendicular to the line starting at that node the node is at a specified distance or the intersection of the perpendicular with another line or arc new 3 43 pyt p fa k E i 5 1 1 d 1 OMS uem new o new 1 a L 2 2 CX 4 news Z from line i from node t from nodes from node select nodes 1 2 and 3 the new node is created at the perpendicular from node 3 to the line joining nodes 1 and 2 i from nodes select nodes 1 and 2 then select a series of nodes using the standard node selection option the new node are created at the perpendicular from these nodes to the line joining nodes 1 and 2
73. aying tabular results for the selected item Sear forces for elernent 14 Steel areas for element 14 Version 12 5 1 9 3 12 06 STRAP 1 9 4 Side Menus Menu tabs are found at the bottom of all geometry side menus Clicking a tab moves you directly to the side menu of the option selected without going pps T sb through the main menu For example i n I Click BB to jurnp directly ta the EE Elements side menu 1 9 5 Help 2 JO STRAP provides the User with extensive on Line Help the entire User s Manual is part of the program and may be displayed at any time The Help for each program item is displayed in a separate topic Help displays one topic at a time on the screen Many options are available for locating and jumping to different topics There are two ways to request Help while running the program Context related help Help for the current option will be displayed on the screen press the key Display the entire User s Manual Click the Help option in the menu bar at the top of the screen and select Contents in the pulldown menu the program will display the Help for the Main menu of the current module e g Geometry main menu To display the Table of Contents for the entire STHAP User s Manual click the button For example the Help topic for the Geometry beam definition menu o Pel Es Menu bar options File Edit Bookmark Options Help Banner f Command Gick options where the e
74. be installed in a separate directory the installation program opens a new directory if the directory with the name entered does not exist To change the program directory click Set the required program modules to Iv Note that the entire program does not have to be installed a useful feature for updates Click to begin the installation For network installation the HINSTALL utility program must be run once from every station where STRAP will be used This utility is installed in the STRAP program directory and may be run either as a DOS command or using the Windows Run option Run the command using the I switch For example G HINSTALL HINSTALL I e Run the LMSETUP EXE program from the NETHASP directory on the CD program either by entering a DOS command or using the Windows Run option The program must be run from the computer that has the network plug attached to it When running STRAP e If you are using plug protection dongle be sure to insert the plug in the parallel or USB port e f you installed the 30 day version the program will request license numbers the first time that you run STRAP Contact your STRAP dealer The Setup option in the initial screen toolbar contains many program configuration options Refer to 1 4 1 1 1 Tutorial STRAP is supplied with several tutorial models The model files are automatically copied to folder STRAP1 DEMO Specify this folder as the Current directory if
75. box To recall scrolled commands click the up down arrow buttons at the right side of the box Example revise the definition for beam 116 move the to the command and click the mouse the command is rewritten at the bottom of the Command Box and the I cursor is displayed at the beginning of the command e Correct the command and press Enter the graphic display will be updated 1 10 3 Retrieve a command from the Clipboard Commands located in any ASCII file may be retrieved via the Windows Clipboard This option is similar to the Batch Mode but allows selected commands to be retrieved rather than the entire file To write the commands to the clipboard e run the program Wordpad Notepad Write a Windows line editor either type in the commands or retrieve an existing file using the File option move the A to the start of the block of commands click the mouse Without releasing the mouse key drag the l to the end of the last command in the block release the mouse Version 12 5 1 10 1 12 06 STRAP key the block should be highlighted File Edit View Insert Format Help Deml alk al a Ea Arial Western 10 B z u el EZZEZEEZENXENEXEEPZCIERZZAGXIETEREGERUE f joint coordinates 100 ta 11 12 5 0 eq 21 D 2 to 2b 6 3 2 75 eg Jb 6 3 2 75 to 31 12 5 2 eg restraints x4 1 ta H x x3 x3 xz x3 11 i member incidences 1ta 10 1 2 For Help press F1 e Select the Edit opt
76. c capacity factor approximate column capacity based on design loads fy steel strength reduction factor for normal design calculations fye steel strength factor for seismic capacity calculations For example a column at the base was designed for a moment 46 2 kn m and the capacity factor for the actual reinforcement 1 07 Steel strength used for regular design 0 87fy while 1 25fy is used for seismic capacity probable strength Mc 46 2 1 07 1 25 0 87 71 0 kn m 8 3 3 Walls The program calculates the distributed reinforcement on both wall faces and in addition determines the concentrated reinforcement required at both wall ends according to the requirements of the relevant seismic Code The area where the concentrated 20g istributed gone reinforcement is required is also calculated Version 12 5 8 4 12 06 STRAP 8 4 Design Procedure 8 4 1 Non seismic For beams columns and walls not designed for seismic forces Define all continuous beams columns including support locations and support widths Walls are identified automatically be the program STRAP wall elements Define all properties not specified in STRAP geometry by dimensions Beams The program designs rectangular tee inverted tee L inverted L and shaped sections Columns The program designs rectangular L shaped round symmetric U and T shaped sections and any solid section created in the CROSEC section generator Note that other shap
77. cel By levels Select all nodes Multiple selection Individual Nodes Select individual nodes by moving the R alongside each node until it is highlighted by the m rectangular blip click the mouse The number of the highlighted node is always displayed at the left hand side of the Dialog box Node 3 TO Cancel End selection You may also type in the number of the node to be selected in the form of a list When all the nodes have been selected press or click the mouse without moving the e Version 12 5 1 9 10 12 06 STRAP In space models more than one node may be at the same screen location and so will be hidden from the viewer the coordinate perpendicular to the screen of these nodes is not identical In such a case the program will display a list of nodes at that location and request the user to select one Select one of the following nodes which are at the same screen location Node 3 Node 53 Move the cursor to the line with the correct node and click the mouse Select by window Define a rectangular window by pointing to its lower left and upper right corners with the gt The program will automatically identify all nodes located in the window In space models more than one node may be at the same screen location and so will be hidden from the viewer In such a case the program will select all of the nodes at that location Select by polygon Define a polygon by po
78. ch element has its own unique local system independent of the local systems of the other elements in the model The X1 X2 and X3 axes or x1 x2 and x3 axes are always perpendicular to each other and the positive direction of the axes are specified by the right hand rule It is obvious that if the directions of any two of the axes are known then the direction of the third axis is easily determined The directions of loads forces moments and stresses are referenced to the global or local axes by standard sign conventions Version 12 5 1 8 1 12 06 STRAP e Global coordinate system refer to 1 8 1 e Local coordinate system referto 1 8 2 e Sign conventions referto 1 8 3 1 8 1 Global Coordinate System The geometry of the structure joint loads and displacements reactions and certain loads are referenced to the global coordinate system The orientation of the structure with respect to the system is arbitrary and is implied by the engineer by node coordinate input Generally one or more global axes are selected to be parallel to one or more characteristic directions of the structure The default convention is e X1 horizontal axis on screen e X2 vertical axis on screen e X3 axis perpendicular to the screen and pointing towards the x2 user Plane structures are always defined on the X1 X2 plane X1 A3 1 8 2 Local Coordinate System Each element of a structure modeled by STRAP has a local reference frame associated
79. ckling assumes that the bracings are attached Member 28 Support at midspan for z major axis bending major and minor axis buckling This support may be defined using the option Define supports at concentrated load points Combined beams Members 8 9 Beam 3 provides buckling support only for the major axis of this column i e members 8 and 9 act as a single unit for minor axis buckling Define major axis buckling and z bending supports at the common node Members 27 28 29 These three members form a single beam Define major axis buckling and z bending supports at the common node Members 30 31 Haunch beam 25 provides buckling support only for the major axis of this column i e members 30 and 31 act as a single unit for minor axis buckling Define major axis buckling and z bending supports at the common node Members 32 33 Similar to 30 31 Define major axis buckling and z bending supports at the common node Version 12 5 7 8 12 06 STRAP 8 Concrete Design 8 1 General The STRAP Concrete Postprocessor is a program for the design of reinforced concrete buildings The program designs beams columns walls and slabs according to the methods outlined in any one of the following reinforced concrete design codes For more information on the Design Assumptions and Method of Calculation refer to British Standard BS 8110 Part 1 1985 Structural Use of Concrete e Eurocode 2 EC2 Design of Concrete Struct
80. d Al Version 12 5 2 9 12 06 STRAP Blank page Version 12 5 2 10 12 06 STRAP P N Restraints Define the location of restrained nodes i e support locations by specifying which nodes have restrained degrees of freedom Each restrained degree of freedom prevents translation or rotation in a specific direction Models without any restrained nodes are unstable i e the stiffness matrix is singular The restraints are normally defined in the Global Coordinate System directions In the case of a sloped support etc restraints may be defined relative to any arbitrary local axis Support locations are specified by moving the crosshair on the graphic display using the mouse or the arrow keys to point to an existing node Select one of the following options All relevant translation and rotation global degrees of freedom are restrained All relevant translation global degrees of freedom are restrained iP BD ED Any other combination of restrained global degrees of freedom 2 r x Define a local support coordinate system a system for supports not parallel to global axes and assign supports to these systems j a m HJ Connect selected nodes by means of Rigid links Master slave nodes zi Delete supports zx T Version 12 5 2 11 12 06 STRAP 2 3 Beams Define beam elements by specifying location designate the end nodes properties define properti
81. d Click on the file description to toggle the status e click the button Note e only the relevant files will be displayed in the menu if you delete geometry files the program will delete the entire model if you delete loads the program will also delete all result files f BEAMD files were created for the model the files may also be deleted Delete BEAMD files Model NBA 5118 Deflections revised load Beams files were created in subdirectory BHO Do you want to delete this directory To delete a model from a floppy diskette select Change current directory and specify A proceed as explained above 1 3 2 2 Make a copy of a model Use this option to create a copy of the highlighted model in the current directory M Geometry file Steel postp tiles I verte I Loadings files I Concrete postp files Dynamic results Stiness matis P Bridge lanes data hime history I Results files M Bridge Hesulbfiles cane Revise the Title optional only files that are marked with a I will be copied Click on the file description to toggle the status press the _ Copy button to begin copying Version 12 5 1 3 3 12 06 STRAP 1 3 2 3 Copy to another directory Use these options to copy a model to another directory another directory or to backup a model to a floppy diskette Note that multiple models may be selected To copy models click and highlight model names in the list to selec
82. dimensions minor axis converted to l section e fthe STRAP section is not symmetric T U and l sections the postprocessor creates a symmetric section using the minimum dimensions Columns e Rectangular round and L sections dimensions are maintained e and U sections If the STRAP section is not symmetric the postprocessor creates a symmetric section using the minimum dimensions sections are considered as Undefined Solid sections created in CROSEC section generator are accepted and the dimensions are maintained 8 3 Seismic design general This section explains the general principles of seismic design for reinforced concrete frames common to all design Codes In general seismic design must insure minimum levels of ductility in the beams and columns and so has more stringent requirements for minimum reinforcement In addition much of the design is based on the moment capacity of the members rather than the design forces calculated by the analysis The moment capacity must be calculated from the actual reinforcement in the beams columns and so the program allows the user to increase the theoretical areas to the actual areas as detailed The design procedure is summarized as follows e beam longitudinal reinforcement is calculated from the design forces but not less than the minimum specified by the Code beam shear reinforcement is calculated from shear forces derived from the moment capacity of the beam but n
83. directory will not be displayed in the model list because the ZZMODEL DIR file cannot be edited by the user This situation may occur in several ways For example e the user defines the model by writing a geometry ASCII file and a loading ASCII file e the GEOMnnn DAT file is corrupted and the user wants to recreate the model from the GEOINnnn DAT file a list of geometry commands maintained by the program when the user defines the model e the model files are available e g on a backup diskette but the ZZMODEL DIR file is not present or corrupted the program Copy to and Copy from options will not locate the models Use this option to add such models to the list Note e the files may have any name e the geometry file must start with the command REPLACE or ADD refer to 1 11 1 Batch mode geometry e the loading file must start with the command ASCII refer to 1 11 2 Batch mode loads The geometry file may be in one of two formats ASCII STRAP batch mode commands the user created a geometry ASCII file refer to 1 11 1 Batch mode geometry for more details on file format STRAP internal format the geometry file was created by STRAP i e binary format This type of file cannot be edited by the user Type in the name of the geometry and loading file optional Note adrive name e g A or a directory path may be entered click the button to display a list of files in the current directory 1 3 8 Recover
84. dware required to run STRAP A personal computer with Windows 98 2000 NT XP Atleast 35 MB of free space on your hard disk The files on the STRAP CD are in compressed format and are copied to the hard disk and expanded by an installation program The program cannot be installed by simply copying the files from the CD To install the program e Insert the CD in its drive Follow the instructions on the CD case back cover Follow the instructions displayed on the screen Three different versions may be installed from the STRAP CD Installation type x C Install STRAP limited to 30 days requires a licence number C Install full STRAP version requires a lock If you select Install full STRAP version the program searches for Personalization files on the CD not required for the 12 nodes or 30 days versions Personalization files il Select the location of the personalization Files GAPER Browse C Click OK ancel Then select the program directory and the modules to be installed Strap Setup Install to je CASTRAPT Browse Installation options Iv Help files Dynamic module I Postten module Steel postprocessor DaF madule Connection design v Concrete postprocessor W Found module Iw Column program Bridge module Lrosec module Space required 4B8358Kb Space available 1 z84152Eb Version 12 5 1 1 1 12 06 STRAP The program should
85. e at intersection of lines Define at the center point of a line between two exist nodes Define at the end pont of a line in a DXF background drawing 2 1 4 Nodes Coordinate system By default the gt moves on the X1 X2 plane even if the display is rotated and node coordinates are defined relative to this Cartesian global system This option allows you to define coordinates relative to a another system A different Cartesian system or a cylindrical system may be defined the will move along the plane of the Cartesian system referred to as the Working Plane or along the arc of the cylindrical system node coordinates are defined relative to the axes of the new system There are two options available Vforking plane wx Xx2 e Working Plane Define the working plane as a different global plane or as a plane formed by any three nodes in the model Refer to 2 1 4 1 e Cylindrical System Define a cylindrical coordinate system The crosshair movement is controlled by defining the angle radius and height from an arbitrary origin Refer to 2 1 4 2 C Defined by 3 nades C Cylindrical system Cancel 2 1 4 1 System Working Plane The working plane is a plane in space along which the gt moves By default X1 X2 is the working plane Any of the three global planes or any arbitrary plane may be defined as the current working plane If the working plane is an arbitrary plane not parallel to o
86. e correct beam and click the mouse Version 12 5 1 9 13 12 06 STRAP Select by window Define a rectangular window by pointing to its lower left and upper right corners with the gt The program will automatically identify all elements with either one or all nodes located in the window refer to Select beams with below In space models more than one element may be at the same screen location only the coordinate perpendicular to the screen is not identical In such cases the program will select all elements at that location Select by polygon Define a polygon by pointing to its corners with the gt The program will automatically identify all elements located in the polygon The program will automatically identify all elements with either one or all nodes located in the polygon refer to Select beams with The polygon is constructed as a rubber band stretched around the defined corners e Atleast three corners must be selected e the program automatically connects the last corner defined to the first corner defined press Esc right mouse button to delete the previous corner e to end the polygon definition click the mouse without moving the In space models more than one element may be at the same screen location only the coordinate perpendicular to the screen is not identical In such a case the program will select all of the elements at that location Select all beams elements All beams elements in
87. e current screen display e the program works on the current STRAP model plane models generate a 2D DXF drawing space models generate a 3D DXF drawing Beams generate a DXF LINE command Elements generate a DXF 3DFACE command e Each STRAP property is assigned to a different layer and drawn with a different color in the DXF file e Dummy beams and elements are drawn in a separate layer e The following is not transferred to the DXF file Dimension lines sections materials text numbering etc 1 6 3 Create a new model from DXF file DXF Import This module converts a DXF format file to a STRAP geometry file It identifies the LINE and mesh commands and converts them to beams or elements as requested by the user Note e that each AutoCAD layer may be specified as containing beams or elements e STRAP property group numbers may be assigned to the generated beams elements according to AutoCAD layer e STRAP property group numbers may be assigned to the generated beams elements according to AutoCAD line color The program handles the different AutoCAD entities as follows e Beam layer each line in AutoCAD is converted to a STRAP beam each AutoCAD mesh element 3DFACE is exploded to a series of lines which are converted to beams Element layer areas enclosed by three or four lines and creates triangular or quad finite elements each SDFACE or surface of a mesh generates a single STRAP quad or triangular element
88. e directions while the x2 axes point in the same direction therefore the x3 axes of these elements point in opposite directions In such a case the sign of the results will be opposite x2 JA x1 JB JB x1 JA When elements are defined in the Graphic Mode the program automatically ensures uniformity in the local x3 axis direction for adjacent elements in order to prevent confusion in the results The x3 direction will always point in the general positive direction of the global X3 axis except for the special cases listed below The program reverses the x1 direction if necessary by interchanging the order of first two nodes To summarize the local axis selection in the Graphic Mode e the local x1 axis lies along the edge of the element formed by nodes JA and JB where ifasingle element is defined JA and JB are the first two nodes selected by the user if agrid line of elements is defined JA JB are the nodes on the edge most parallel and closest to the base line e the x2 axis lies in the element plane perpendicular to x1 and points in the direction of the other nodes e the direction of x1 is from JA to JB The program determines the direction of the x3 axis using the right hand rule If x3 does not point in the direction closest to the global X3 axis the program interchanges the JA and JB nodes Special cases i the element plane is parallel to the X3 axis x3 points in the direction closest to the global X2 axis
89. e the into the X3 text box in the Dialog Box Either type in the correct value or click the button until the correct value is displayed Note that if you click and hold the left mouse button until the is in the Dialog box then the X1 and X2 coordinates in the box will be those at the location when the mouse was clicked Define the X1 X2 coordinates as explained in the Plane Model example above Note that the mouse can move along any plane referred to as the Working plane By default the program selects the Global X1 X2 plane as the working plane However the user may select any of the other global planes as the working plane or define any plane in space by specifying three nodes Version 12 5 2 3 12 06 STRAP Additional options ees gt Define with same coordinates as existing node Specify that one or more of the global coordinates is identical to the same coordinates of an existing node Same as an existing node select the identical global coordinates by turning on their checkboxes F8 click the button select an existing node Line inter een Node 88 Cancel C coords Perp from C a line Move the to an existing node the gt will move only in the allowable directions and click the mouse or type in the node number in the dialog box and press Enter e Define a node at intersection of lines Intersection by nodes Using the e define two lines by pointing to their st
90. ed of pinned beam elements only Dynamic Analysis Dynamic modal shape analysis and natural frequency calculation Seismic response spectrum analysis Forced Vibrations and transient Response Design Postprocessors Structural steel design and member selection according to AISC LRFD AISC ASD Eurocode 3 BS5950 AASHTO LRFD ASD CAN CSA 16 1 IS 800 and AISI ASD amp LRFD Cold formed Reinforced concrete design for beams and columns according to ACI 318 CSA A23 3 Eurocode 2 BS8110 and 1S 456 Bridge design Defines lanes calculate influence lines and maximum minimum results for each result type for all points on a bridge model Foundation design Design of spread footings The most general and comprehensive module in the package is Space Frame It enables the engineer to model any type of space structure using one and two dimensional elements In order to simplify the use of the programs especially for engineers unfamiliar with computer structural analysis the system also includes modules for more specific types of structures For example the Plane Frame module solves plane frames only Space frame can also be used to solve plane frames but it is more convenient to use Plane frame as the data required is simplified and the possibility of user error is reduced accordingly Version 12 5 1 0 2 12 06 STRAP 1 1 Installing the Program Before starting the program installation make sure that you have the har
91. efined Linesections Sections composed of a series of connected lines each with a specified thickness Segments may be defined in any direction diagonal Several subsections may be defined to form a section The properties may be copied to STRAP geometry Tables of cold formed sections may be added to the STRAP property tables Properties calculated include Shear center warping constant torsional moment of inertia and torsional flexural buckling constant Solid sections Sections formed by a closed contour Several separate contours may be defined to form a section additional contours may be holes The properties may be copied to STRAP geometry Properties calculated include Torsional moment of inertia exact Version 12 5 1 5 1 12 06 STRAP 1 5 4 Combine results of two projects Use this utility to combine the result files from several models This option is essential in models where the geometry changes for different loading cases e g supports properties etc and the structure must be run as two or more separate models but where it is necessary to search all loading cases from all of the models in the various design post processors the Stage option 2 10 can achieve the same result more efficiently The number of nodes or elements in the two models that are combined do not have to be identical but the node element at the same location in both models must have the identical numbering By combini
92. efined in a text box as 2 To revise text in a text box e use the mouse to move the arrow to the text box and click the left mouse button e edit the text in the box Command button Command buttons initiate an immediate action In the dialog box above e displays the graphic results according to all other options selected in the dialog box Cancel l E closes the dialog box the option is canceled and all options are returned to the values present when the dialog box was entered 1 9 3 Shortcut Menus A Shortcut Menu is a useful pop up menu that provides options specific to a certain object in the model Right click an object such as a node or element to display the Shortcut Menu for that particular object e Geometry Beams Elements Right click on nodes beams or elements For example a right click on a node displays a Shortcut Menu that lets you select all node related options or display data for the selected node Henumber nodes Delete nodes Move nodes Restraints ses Renumber node 83 k Delete node 83 Move node 83 Restraints for node 83 k Spring for nade 83 Data for node 83 Loads a right click on a beam displays a Shortcut Menu with beam load definition options etc e Results Moments for element 14 14 5lresses at 2 for element 14 Principal Stresses at 2 ele 14 Design moments for element 14 a right click on a node beam element displays a Shortcut Menu with options for displ
93. el to a global direction assign a local restraint system to the node as explained in Springs local Do not define the global components of the spring constants using S sin 0 and S cos 6 Version 12 5 2 15 12 06 STRAP 2 6 Copy Copy is a powerful option which enables the user to copy a block from the model including nodes elements properties and releases to a different location r3 All elements in the copied block are drawn parallel to the original ones The location of the copied copy block is at a specified distance from the original gt The copied block may also be rotated with respect to the original block The program may stretch SEC or shrink the dimensions of the block but will always maintain the same node element layout rotate RA Create a mirror image of the original block about an axis of symmetry mirror Note e more than one copy of the block may be created with one command e the program will not generate a new node at the location of an existing node but will use the existing node when creating the elements in the new block e the program will not generate a new element at the identical location of an existing element e the copied element will be assigned with the property group number of the original element e Releases are automatically copied Beam local axes Copy rotate Mirror The program tries to rotate the local axes along with the rotation of the block For example a beam with x2 pointing
94. elect Files in the menu bar select New model in the pull down menu or click the ol icon in the icon bar define the model title Enter title for new model max 70 char Version 12 5 1 2 2 12 06 STRAP The program then displays the Geometry preliminary menu Units Meter ton Select the model units Dod revise the model title Model type C Plane frame HH C Grid in Space frame E CTruss chilis Specify the model type select a method for creating the model H ERE Select the method for defining the new del aen defined model Display width 0 3 to 30 Display height 3 to 30 Cancel m NS There are two methods for defining a new model Select a model from the STRAP library of standard structure types Define the geometry loads and load combinations The basic model created by the wizard may be revised later using any mone of the STRAP geometry and loading definition options jijini The program displays a blank screen Define the geometry and loads from scratch using any of m the STRAP geometry and loading definition options 1 2 2 Amend rerun an existing model To revise a model that appears on the list Torevise the geometry move the cursor to the model name in the list and double click the mouse To directly access any other part of the program loads results etc move the cursor to the model name in the list and click the mouse
95. element surface will be incorrect Version 12 5 5 6 12 06 STRAP 5 3 3 Results along a line To display the results plotted along a section through the model For example This option calculates the results at all points along any line arbitrarily drawn through the model using the linear stress distribution assumed in each element Therefore this option will show a local stress or moment concentrations at element corners and the results correspond to those in the tables If a section is plotted along an element boundary the program uses the results of one of the adjacent elements and does not average the values of all the adjacent elements The user selects the plot of the result type along the line or perpendicular to the line e X always refers to the axis along the line of the section e Y always refers to the axis perpendicular to X in the element plane Zaxis is perpendicular to the plane of the element Plane models The positive direction of the Z axis of all elements is the positive direction of the global X3 axis i e if the local x3 axis of adjacent elements point in opposite directions the result diagram will still be continuous Space models The positive direction of the Z axis of each element is the positive direction of the local x3 axis of the element if the local x3 axis of adjacent elements point in opposite directions the result diagram will not be continuous The results are drawn above and bel
96. em Typical input for the self weight example are SELF X1 B 10 11 12 o X3 1 4 B 1 TO 90 The program checks the validity of every character entered an illegal entry will cause the computer to beep and the character will not be displayed on the screen Version 12 5 1 10 3 12 06 STRAP Blank page Version 12 5 1 10 4 12 06 STRAP 1 11 Batch mode BATCH processing is a method where the model files are created external to the program STRAP has facilities for processing geometry loads and load combinations solving the model and generating input output data files without using the interactive graphic interface geometry loads and or combinations may be defined by the user by typing commands in an ASCII file using any editor program e models created in batch mode can be added to the model list using the Add a file to model list option in the File pulldown menu and can then be solved etc alternatively the model can be solved using the STBatch utility refer to the STBatch manual e for all models input output ASCII data files in user specified format can be generated by the ST Batch utility 1 11 1 Batch mode Geometry There are two methods for defining STRAP geometry via external files Using the Clipboard refer to 1 10 3 Creating and importing an ASCII file The file format is as follows 1st line REPLACE ADD where REPLACE the program will use this file instead of the existing
97. enerating ASCII files with geometry load and or result data in user specified format Refer to the STBatch manual or STRAP Help for more details 1 5 1 Footing design Design reinforced concrete spread footings Refer to 11 1 5 2 User steel section table This utility module allows you to e build a customized user steel section table for the STRAP geometry and the Steel postprocessor Sections may be copied from any of the standard steel tables British European or American or new sections may be defined by entering their dimensions the program will calculate all the section constants e add cold formed sections to the standard steel tables Note e the user steel table is always stored in PROPTABS DAT and must be in the program directory note that new section types may also be defined for convenience ifauser steel table has been created The user steel table option is displayed in the Section table menu 1 5 3 Compute section properties A module that calculates the properties of geometric sections area moment of inertia center of gravity etc Also available as a stand alone program CROSEC Refer to 12 The program can calculate all properties that are required for the design of cold formed light gauge sections All line sections with any arbitrary shape defined in this program may be transferred to the STRAP steel postprocessor and can be calculated as cold formed sections Two general types of sections may be d
98. es 50 along the working plane only 2 1 4 2 Cylindrical Coordinate System Coordinates may also be defined relative to a cylindrical coordinate system If a cylindrical system is specified the coordinates used to define node locations are e radius R instead of X1 e angle Ang instead of X2 height H instead of X3 A cylindrical coordinate system has a central non cylindrical height axis which may point in any direction and which passes through a selected origin node To cancel a Cylindrical System define a Working Plane Select the global non cylindrical axis and its location Cylindrical coordinate system Cyl system height axis The origin location depends on the option used to define the amp Global X3 axis height axis f Global Xl axis Height axis System origin C Global X2 axis Parallel to global axis according to option selected in menu C Defined by 2 nodes Defined by 2 nodes at first node selected Perp to circle at center of circle C Perp to circle defined by 3 nodes For example if X3 is chosen as the height axis and the origin is Cyl t igin e iia ede L set at any arbitrary location the cylindrical coordinate system is Global system origin b Height axis Parallel ta Defined by a node x3 Defined by coordinates s a d 7K Origin node of cylindrical system The options Line equal Line general and Grid may all be used while a cylindrical coordinate system is in effect A
99. es A l dimensions or a steel shape material Select a program material or define a new one local axes specify the local x2 x3 axis directions orientation specify major minor axes orientation relative to the local axes releases define pinned connections rigid offsets define rigid segments at the beam ends Select one of the following options e Define one beam element by identifying its end nodes or i define Define a series of beams all lying on a straight line The beams are defined by identifying the nodes at the start and the end of the line the program automatically locates all intermediate nodes and connects them with beams or Define a continuous string of beams where the start node of any beam is the same as the end node of the previous beam Define a parallelogram grid of beam elements The grid is defined by identifying the three corner nodes on the base line and the height line of the grid the program automatically searches for all and intermediate nodes and creates a grid of beams Define a series of beams that all start on a common line and end on a different common line Delete a beam already defined Define section properties including material and assign them to beams i x E ed T Define pinned end connections Define rigid offsets at the ends of beam elements and assign them to the beams Renumber a beam element already defined gz m em mh re mz sE ETEL
100. es are converted automatically by the program or ignored refer to Define Specify the default parameters for all beams columns walls Define parameters for specific beams columns if different than the default parameters Examples of parameters that may be defined Beams reinforcement and concrete type stirrup parameters moment redistribution percentage shear reduction etc Columns reinforcement and concrete type Walls effective length factors allowable bar diameters structure type braced unbraced etc Compute the results The beams columns walls are designed in sequence without any prompts for information by the program Therefore all design data and parameters must be defined before the design begins The program carries out the following calculations Beams calculation of moment and shear envelopes from all load combinations automatic moment redistribution optional shear reduction at span supports optional calculation of reinforcement steel required at all supports and spans automatic stirrup detailing with variable spacing deflection check span depth ratio BS8110 EC2 IS456 NBr deflection based on effective moment of inertia ACI CSA Columns determination of the critical STRAP load combination calculation of magnified additional moments for slender columns walls selection of reinforcement arrangement that is able to withstand applied bending moments and axial force for all load combinatio
101. ess than a specified percentage of the negative moment capacity at the support The program adds additional top bottom reinforcement as required Shear The seismic design shear forces Ve are calculated from the probable moment strength of the beam together with the factored beam loads Map L Ww Map MIX IOGIETIJ v EEE fv Mocap L Map R RL Rw R t Ya Meapi MeapR Ry The program also checks the beam for the design shear from all load combinations Note that Mcap is calculated from the actual reinforcement it is important that the user increase the theoretical values to reflect the actual detailing Stirrups links are calculated from Ve subject to the minimum requirements in the Code In general closed hoops at reduced spacing are required at all locations where plastic hinges may form and to a distance x beyond Possible plasti ossible plastic fat both hinge region y Lee ends x X Min stirrups EE ME 9H ds LN Hoops at Lf reduced spacing 8 3 2 Columns Moment and axial load The columns are designed for all load combinations defined by the user Column areas are not reduced for lightly loaded columns Mc In addition all codes require that the sum of the column flexural strengths at a column beam joint exceed the sum of the nominal beam flexural strengths strong column weak beam i e Ib F where e Mb is calculated from the actu
102. estart the solution from the point of interruption select Resume solution when the following menu is displayed solution was previously interrupted Hestart from beginning 4 2 Solution method The program solves the model by the stiffness method This method solves models on the basis of joint equilibrium equations in terms of stiffness coefficients and unknown joint displacements The method formulates the matrix equation K d P where K the stiffness matrix and is a function of the geometry d the nodal displacement vector P the applied nodal forces vector The equation is solved for the unknown node displacements and hence the internal element forces or stresses The stiffness matrix is a square matrix where each side is approximately ndof nj where ndof is the number of degrees of freedom per joint and nj is the number of joints in the structure and is symmetric about the diagonal starting in the upper left corner of the matrix Most of the values in the matrix are equal to zero The non zero values are usually clustered along the diagonal forming a diagonal band The width of this band is called the bandwidth The significance of the bandwidth is that its size is the most important factor in determining the solution time The bandwidth size is dependent on the way the nodes and elements in the model are numbered For example numbering the nodes in a multi story model vertically instead of horizon
103. etrieves from STRAP e the reactions for all STRAP load combinations at these nodes force and moments e the column dimensions if possible from the section of the member attached to the node Upon selecting the Footing postprocessor option in STRAP the user can choose to design All several footings The program automatically designs the footings for the group of supports selected Design parameters may be defined for the entire model Results for the entire model are displayed in tabular form Results for footings previously designed with the Single footing option will not be overwritten Single footing The program automatically designs the footing for the support selected Design parameters may be revised for the individual footing Load cases may be added revised or deleted Results for the individual footing are displayed in graphic form Results for footings previously designed with the All Several footing option are overwritten Current results for any footing may be viewed by selecting Single footing and then selecting the associated node Refer to 11 2 1 Note footings are assumed to be oriented according to the local x2 x3 axis of the column e the program always transfers the column dimensions as a rectangle that bounds the actual section dimensions The loads are assumed to act in the center of this rectangle e for columns defined by properties A l the program transfers zero dimensions and the postprocessor begins the
104. evel and increment in edit boxes D Click _ Select E to highlight these levels in the list or _Remove E to remove the highlight e Click ox the program will identify all nodes at the selected levels Note All nodes within the tolerance distance C will be selected Select all nodes All nodes in the model will be selected Note e nodes not displayed because of the Zoom option will be selected nodes not displayed because of the Remove elements option all beams elements attached to these nodes are removed will not be selected Multiple selection Turn on the checkbox if you want to define several windows polygons or lists for the same command After every window etc the following menu is displayed Add more nodes to selection Hemove nodes from selection End selection Continue without selecting more nodes Add more nodes Define another window polygon etc for the same command Remove nodes Delete members from the list window etc already defined for this command Version 12 5 1 9 12 12 06 STRAP 1 9 11 2 Beam Element Selection Many options include instructions to select one or more elements When selecting an element the element nearest to the P is highlighted with a rectangular blip m The number of the highlighted element is always displayed at the left hand side of the Dialog box You may also type in the number of the element to be selected BEAM SELECTION x P
105. ever the sign of the moment at JA will be positive in the tables xz 320 135 M3z 1 333 C e x1 x3 m JA JB Version 12 5 5 8 12 06 STRAP Shear V2 V3 A positive shear force acts in the positive direction of the local axis Axial The sign of the axial force is positive in the x1 direction of the beam A positive axial force value at JA along with a negative value at JB always indicates that the beam is in compression For trusses only the result at JA is displayed i e a positive value indicates compression the value at JB may be different if an intermediate axial load is applied but the result will not be displayed 5 4 1 2 Sign Conventions Quadrilateral and Triangular Elements The results are relative to the element result coordinate system Refer to 5 2 The forces are per unit width i e FX 50 2 means 50 2 ton m kN m kip ft etc STRESSES SX stress in element result X direction on the Z surface SY stress in element result Y direction on the Z surface SXY shear stress on Z surface SX stress in element result X direction on the Z surface SY stress in element result Y direction on the Z surface SXY shear stress on Z surface FORCES stress resultants in the result coordinate system The element forces are computed directly from the element stresses FX T SX SX FY 2 SY SY FXY SEXY 8XY PRINCIPAL STRESSES principal stress at each face derived fro
106. fter the following example For the following example the ASCII file would be 3s REPLACE JOINT COORDINATES COORD 2 10 0 TO 6 0 15 EQ 7 10 0 TO 12 10 15 EQ RESTRAINTS X1 X2 X6 1 7 PROPERTY NUMBERS 11 TO 10 2 11 TO 15 MEMBER INCIDENCES 1 TO512 6 TO 107 8 11 TO 157 8 MATERIALS E 400m CONC Boum ucc ue PROPERTY DEFINITION 5 5 1 A 0 1 0 002 BEAMS amp 2m 0 02 m 2 A 0 2 0 02 5x30 15 0 m GEOINnnn DAT The current geometry for each model is stored in a binary file named GEOMnnn DAT where nnn can be verified by selecting the Display all model files option in the Files pull down menu on the main menu bar However STRAP simultaneously creates for each model an ASCII data file that contains all of the geometry data that was defined interactively in the form of commands The command formats are explained in detail in the Command Mode manual The file name is GEOINnnn DAT This file may be edited or updated external to the program using a screen editor STRAP can then be instructed to use this file instead of the existing geometry file GEOMnnn DAT as the source for the model geometry When you choose the Geometry option in the Main Menu bar the program reads the first line of the GEOINnnn DAT file If the first line is IGNORE the program will ignore this file and use the GEOMnnn DAT file only This is the normal case because when the model is entered interactively the program automatic
107. ghlighted with a rectangular blip m The levels is 0 Pe between the number of the highlighted wall is always displayed at the left hand considered an qag 4 nodes selected side of the Dialog box You may also type in the number of the wall individual wall to define the and maybe M lewels to be selected selected i separately J Individual walls Select by window Select by window Cancel Select by polygon select by polygon Select all walls Select all walls Hefer to beam element selection Select walls with One node in the window polygon Both nodes in the window polygon Multiple selection Limit selection by section Select with one node both nodes One node Walls 1 2 and 3 are selected Both nodes Only wall 2 is selected i One node in the window polygon Window Jo all walls with at least one end node in the window polygon will be a M Polygon selected a Both nodes in the window polygon m attachment Hag only walls with both end nodes in the window polygon will be node selected Note that the program only considers the nodes where the wall reference point was attached to the model Multiple selection Refer to beam element selection Limit selection by section Selection by property type Further limit the wall selection according to section type Set to NO sections of walls that should not be selected Yes walls in the section group will be selected Hm vem E
108. he closest possible global direction in the main model Restraints defined according to a local system will be rotated to the same orientation relative to the sub model Version 12 5 2 20 12 06 STRAP 2 10 Stages Define construction stages for the current model e the default stage is the Whole model it represents the final structure and contains all elements and the properties and supports springs present at the end of construction all other stages represent intermediate steps during construction beams and elements may be removed or restored but cannot be created different properties and supports may be assigned and only specified load cases may be applied The program treats each stage as a separate model and calculates the results based on the stage geometry and the applied load cases The stages are defined and activated in this option elements properties restraints etc are applied removed from the stages in the various Geometry and Load options For example Stages Xx No Stage name Whole model Stage Al Move up Stage BI Move down Add Delete Cancel Version 12 5 2 21 12 06 STRAP kkk Blank page Version 12 5 2 22 12 06 STRAP 3 Loads The program can solve the model for multiple load cases Each load case may consist of joint loads beam loads element pressures and support displacements Load cases may be combined to form a new load case Beam a
109. he nodes or elements such as bridges Global loads can be entered directly or may be stored and recalled from a file 3 7 Solid loads Define temperature loads or self weight for solid elements All other loads pressure linear loads concentrated loads etc must be defined by applying them to beams or plate elements dummy or regular defined parallel to the solid elements surfaces 3 8 Wind loads This option generates wind loads according to Code requirements The user defines e the outline of areas referred to as panels or selects beams and defines the perpendicular panel width e the direction in which the wind acts e the height direction of the panel various Code parameters The program calculates the wind pressure distribution on the panel according to the Code and distributes the load to the nodes beams elements in the panel area Version 12 5 3 3 12 06 STRAP model Wind distribution Pr direction In general each wall or roof plane should be defined as a separate panel Note e Wind pressures are applied to the nodes beams elements using the same methods that are used to apply global area loads e Dynamic effects are not considered The wind loads may be generated by specifying e a contour area the global area loads calculated by the program are applied to either nodes beams or elements e aseries of beams and the perpendicular width the program applies linear beam loads this i
110. iagrams Care must be taken to define the correct boundary restraints along the line of symmetry An error in defining the proper restraints will lead to incorrect results Version 12 5 1 7 3 12 06 STRAP 1 7 2 Inputting the Model The program continuously displays the model graphically and updates the display automatically after every input command thus enabling the user to instantaneously check the accuracy of the input STRAP allows you to use one of three input modes Graphic Mode The model is defined by moving the crosshair using the mouse arrow keys to identify node locations define elements assign properties loads etc All parameters such as current crosshair coordinate are displayed at the bottom of the screen and are updated continuously Only a limited number of parameters need be typed in Nodes and elements are numbered automatically by the program when generated Numbering is always consecutive unless specified otherwise The numbering may be revised by the user The final numbering pattern should be one that will cause the results to be printed in a logical sequence Command Mode The model is defined by typing commands in standard format The geometry is displayed simultaneously on the screen and is updated after every command The numbers of all nodes and elements are specified by the user The system of numbering should be such that a minimum number of input commands are required This varies from structure
111. inting to its corners with the gt The program will automatically identify all nodes located in the polygon The polygon is constructed as a rubber band stretched around the defined corners e Atleast three corners must be selected e the program automatically connects the last corner defined to the first corner defined press Esc right mouse button to delete the previous corner e to end the polygon definition click the mouse without moving the e n space models if more than one node is at the same screen location the program will select all of the nodes at that location Example select nodes 1 2 4 5 and 7 1 2 4 7 8 and 9 P g 7 P g B 4 t B 38 1 2 3 Version 12 5 1 9 11 12 06 STRAP By levels Select all nodes at selected levels coordinates with nodes Level selection Height direction B C Click and highlight levels in the list Use Multiple level selections to add remove a group The highlighted levels will be selected Goole ote es Add remove highlight for multiple levels in the above list box From level To level Increment a Select Remove OK Cancel e The program displays a list of the levels parallel to one of the global axes A A different global axis may be selected in the Height direction list box B e Select levels by clicking and highlighting them A Equally spaced levels may be selected by entering the coordinate of the start level end l
112. ion from the top menu bar Select the Copy option from the pull down menu e The block of text is now in the clipboard exit the Write program To retrieve the commands from the Clipboard into STRAP Select the Edit option from the STRAP top menu bar e Select Paste commands from the pull down menu The program reads the commands adds them to the Command Box and updates the graphic display If the program encounters commands with format errors or commands that generate warnings i e redefinition of existing nodes it pauses and displays the following menu STNTAS ERROR Ignore command Quit copy Edit command The command is displayed in the Command Box at the bottom of the screen edit the command as explained in Revise a command The program will then continue to the next command in the clipboard Ignore command The program will ignore the current command and continue to the next command in the clipboard Quit copy The program will ignore the current command and all following commands in the clipboard 1 10 4 Command Format General All data is input in free format There must be at least one blank space between one data value and another including words numerical values and special symbols without exception The commands must be in the format specified by this manual For example to define the self weight of beams as a load on the structure the manual specifies the command Version 12 5 1 10
113. iscellaneous The grid is automatically updated every time the Step value is revised e fthe step value is small relative to the screen dimensions the density of the dots will be too great In such cases the program will display the dots with a spacing equal to a multiple of the Step value several clicks of the arrow key will be required to move from a dot to the adjacent dot e A cylindrical grid will be displayed when a cylindrical coordinate system is in effect note that the mouse can be used for a cylindrical coordinate system only when the Grid is displayed 1 9 2 Dialog boxes STRAP uses Windows Dialog Boxes to request data and to provide information Most dialog boxes contain options each one asking for different information After all required information is supplied a Command Button is pressed to carry out the command and return the program to the previous menu or dialog box Dialog boxes also provide information warnings and error messages Version 12 5 1 9 1 12 06 STRAP A typical Windows dialog box contains several types of standard option styles For example Graphic display List box Display type Element results contour map Result type Moment in X direction Option Load case button Load case Combination LOADING 1 C Envelope Check Parameters box Fill contour regions with colour Text Number of contour lines 2 box Change contour lines values Command button SEES List box
114. ith edge beams combined frames and shear walls etc The method of solution is the well known stiffness method It assumes a linear elastic model and small displacements The program solves the stiffness equation IK d P where K the structure stiffness matrix d the unknown nodal displacements P the applied nodal forces After solving the equation for the unknown joint displacements the program calculates the internal forces and stresses in the beams and elements Although using STRAP does not require knowledge of computer structural analysis it is recommended that the user familiarize himself with the basic theories of the stiffness method and finite elements Version 12 5 1 0 1 12 06 STRAP The STRAP system consists of the following modules Static Analysis Plane frame analysis Analysis of plane frame models all loads applied in the plane of the model composed of beam elements and two dimensional plane stress elements Plane grid analysis Analysis of plane grid or plate models all loads applied perpendicular to the plane of the model composed of beam elements and two dimensional plate bending elements Space frame analysis Analysis of general space structures composed of beam elements and combined plane stress plate bending elements Typical structures are space frames shear walls combined with frames roof shells folded plates water tanks etc Truss Plane and space truss analysis compos
115. l adai _ The last five folders selected in the Change current directory option zu p A e tants are displayed at the bottom of the of the File menu Clicking one of these lines will make that directory the new current directory 3 D STRAFIS433a SOASTRAPT michael Exit New model Refer to 1 2 1 e Print Refer to 1 3 1 Delete Refer to 1 3 2 Copy to another directory Copy from another directory Make a copy of a model e Change current directory Refer to 1 3 3 Copy to a ZIP file Refer to 1 3 4 Unzip a model Refer to 1 3 5 Display all model files Refer to 1 3 6 e Add afile to the model list Refer to 1 3 7 e Recover model geometry Refer to 1 3 8 Version 12 5 1 3 1 12 06 STRAP 1 3 1 Print Use this option to print all or selected input results and saved drawings in any order for any model in the list without running the model e Specify the tables to be printed by clicking on the Beam results element results tabs e Specify the load cases combinations to be printed in the Loads tab e Print input output data for specific elements nodes only by specifying one or more views in the Views tab Il Include saved drawings to add drawings created with the Save for print edit drawing option The current selections are displayed in the Overview tab Click to start printing Print parameters Beam results Elements results Result units VIEWS OVERVIEW Geometry Load
116. l line but pass through the additional nodes x2 Node 3 existing nodes Pd Select three nodes 30 i e X1 of the first node X1 of the new node e X2 of the second node X2 of the new node e X93 of the third node X3 of the new node 2 1 2 Line of Nodes Equal Spacing Use this option to define a line of nodes where the spacing between them is equal To define the line define the start node of the line as explained in 2 1 1 Single node define the end node location The dialog box at the bottom of the screen is dx 3 Cancel Screen H where X1 X2 e3 location on the screen global coordinates dX1 dX2 dX3 distance from the start node Move the P until the correct coordinates are displayed or type in the correct values in the text boxes e Specify the number of segments For n nodes including the end nodes there are n 1 segments Version 12 5 2 6 12 06 STRAP Example 0 0 1 3 5 moveto X1200 X2 0 0 click the mouse moveto X1260 X2 0 0 click the mouse In 19 ts 15 e specify four segments Additional options refer to 2 1 1 Define with same coordinates as existing node Define end node at intersection of lines Define at the center point of a line between two exist nodes Define at the end pont of a line in a DXF background drawing 2 1 3 Line of Nodes Unequal Spacing Use this option to define a line of nodes where the spacing between them is not equal
117. length i e sum of loaded strip widths may be limited by the user 9 3 How to use the Bridge Module Version 12 5 9 1 12 06 STRAP STRAP Create a model of the bridge in the STRAP geometry module Define all loads other than the bridge loads in the STRAP loading module Solve the model optional at this stage but before STRAP results are displayed design postprocessors are accessed etc Return to the STRAP Main menu Select Design in the menu bar and Bridge module in the pull down menu Bridge Module Define lanes Set lanes in side menu and click the Define icon Define the start and end nodes of each segment the lane width and the number of strips per segment Select the method of distributing the loads to the model select Options in the menu bar select Load direction to specify the Global direction in which all loads are applied select Load distribution in the pull down menu and specify the element types that the loads are applied to beams specific beams elements Solve the model Select Files in the menu bar and Solve in the pull down menu The program will return to the bridge module after completing the solution Display influence lines Select Results in the menu bar and graphic display select Draw influence lines in the pull down menu tabular display select Display influence lines table in the pull down menu Define lane loads set lane loads in side menu and click the Define icon
118. li the element lies parallel to the X2 X3 plane x3 points in the direction closest to the global X1 axis AZ Pi Ad JA i J ii 1 8 2 3 Triangular Finite Elements The definition of local axes is similar to that for quadrilateral elements x2 JC JA JE x3 is perpendicuclar ta the plane of the element x1 Version 12 5 1 8 5 12 06 STRAP 1 8 2 4 Wall elements The default local coordinate system for wall element segments is identical to the default system for beams The program assumes that the wall local x1 axis is parallel to the height axis specified when defining the wall and points in the positive direction of the height axis height axis x1 x1 i Ad global top top 4 bot ca bot global x3 x3 a General case ih Special case x1 parallel to 3 X1 parallel ta height axis X1 parallel ta height axis X3 general sa global direction XJ general s2 global direction xz right hand rule Xx3 right hand rule The default local axes cannot be revised 1 8 3 Sign Conventions Forces and Moments Forces and moments are referenced to a local or global coordinate axis Forces positive forces point in the positive pule direction of the relevant coordinate paint thumb in positive direction of axis axis then fingers point in positive direction of moment e Moments Moments act about a local or Example global coordinate axis The sign of
119. m ft kip ft etc e MX is the moment in the direction of the element result X axis and not the moment about the X axis see Figure below Therefore the stress SX corresponds to the moment MX Similarly MY is the moment in the direction of the element result Y axis and not the moment about the x2 axis astress distribution with tension on the z face results in a positive bending moment refer to 5 4 1 2 Element sign conventions e For the equations relating moments and forces to stresses refer to Element sign conventions Example moments sorted by combinations El Comb hix My My Hot 1 1 1030E 01 5686E 05 2443E 4 0l l 2 e UbBUE 11 T17 Z7 E 04 Z885E 40l e Maximum values are calculated from all of the result points e Rot indicates the angle between the local x1 axis of the element and the result X axis The result axes may be defined in the Element result coordinate system option If no specific axes are defined the program uses the default result axes Refer to 5 2 1 Version 12 5 5 12 12 06 STRAP 5 4 5 Reactions The program sums at each node all of the applied loads and element result end forces of the attached elements for all degrees of freedom The sum for degrees of freedom at nodes that were not defined as restraints should be equal to zero The reactions are X1 X2 X3 reaction force parallel to the global axes A positive force is in the positive direction of the axis X4 X5 X6 moments abou
120. m fibre The equations are in the form Te 7 rey all where oe is the relevant stress from the external loads Plotting all of the possible solutions for each of the four conditions gives four intersecting lines 1 2 2 3 3 4 4 1 in the adjacent diagram any combination of P and e within the enclosed area will result in acceptable stresses in the specific cross section Version 12 5 10 4 12 06 STRAP 11 Foundation Design 11 1 Program Specifications Program FOUND designs reinforced concrete spread footings The program features are design for axial force and biaxial moments in same load case eccentric column allowed in both directions Quick design of several footings by entering data in table multiple load cases up to 25 automatic design of base dimensions and reinforcement according to Code requirements automatic design of height according to punching and shear including sloped upper surface automatic design and detailing of reinforcement according to Code requirements user defined dimensions may be checked design units may be specified by the user graphic output of footing plan and section to scale and in colour DXF file of graphic output may be created The following symbols are used by the program EY m Note the sign conventions for positive eccentricity of the column about the center of the base positive applied moments and axial load Version 12 5 11 1 12 06 STRAP 11 2
121. m the Mohr s circle equations fa 2 2 P sxesyY sx sY MIN SXY where MAX and MIN are the algebraic maximum and minimum not the absolute _ MAX MIN S MAX MAX 2 maximum shear ANGLE the amount in degrees the element X axis must rotate counterclockwise about the Z axis to coincide with the principal stress axis 03 1 2x8XY a E Note when the X axis coincides with the maximum stress axis Y coincides with the minimum stress axis MAX SHEAR occurs on a plane offset 45 from the principal axis Shear is zero in the principal stress directions The positive sign conventions for all stresses and forces are shown in the figures below Version 12 5 5 9 12 06 STRAP e MOMENTS Moments relative to the result coordinate system at the centre of the element The moments are computed directly from the stresses by MX T SE SX MY 32 SY SY MXY SEXY 8XY Note The sign convention for moments is illustrated in Figure b below referring to the equation above for calculating MX it is obvious that a stress distribution with tension on the z face results in a positive bending moment MXis the moment in the direction of the element result X axis and not the moment about the X axis see Figure below Therefore the stress SX corresponds to the moment MX Similarly MY is the moment in the direction of the element result Y axis and not the moment about the Y axis
122. messages are listed on the screen and written in an ASCII file ERRS LST e The program does not check that entire geometry has been defined e g restraints 1 5 7 Create a STAAD geometry input file Create STAAD format geometry and load files for the current model 1 5 8 Create steel detailing files Create a structural steel detailing file in one of the following formats e STRUCAD e SDNF The program writes the model geometry and the beam end results to the files The steel section written to the file is the current one in STRAP geometry different sections selected in the Steel Postprocessor must be transferred to the geometry using the Exit and update geometry option in the postprocessor Version 12 5 1 5 2 12 06 STRAP 1 6 DXF options 1 6 1 Convert metafile to DXF Use this option to create a two dimensional DXF file of any STRAP graphic display The metafile is created by selecting Print drawing in the Output pull down menu on the menu bar and then selecting Metafile in the Send output to box When this option is selected the program displays a list of the Metafiles extensions EMF WMF in the current directory Select the file to convert 1 6 2 Convert STRAP file to DXF DXF export This module converts the STRAP geometry file to three dimensional DXF files This option differs from the STRAP Print drawing option and subsequent Convert Metafile to DXF in that it creates a full 3D model instead of a 2D image of th
123. minor axes Version 12 5 1 8 3 12 06 STRAP raf l x3 Mon HS mar axis 8 MIGF SX IE 5 Options are available for aligning the local x2 or x3 axes with an existing node or any user defined plane Example 29 Section A 4 define the local axes of beams 1 to 5 as shown e beams 1and2 specify that the local x2 axis is parallel to the global X1 X3 plane e beams 3 4 and 5 specify the local x2 axes as pointing in the direction of node 29 The x3 axes are determined by the program according to the right hand rule 1 8 2 2 Quadrilateral Finite Elements Each two dimensional finite element has a local coordinate system associated with it The local x1 and x2 axes always lie in the plane of the element and x3 is always perpendicular to the element The directions of the local axes are determined by the location of the element corner nodes e the local x1 axis lies along the edge of the element formed by JD nodes JA and JB and is positive in the direction of JB where JA and JB are the first two corner nodes defined by the user e x2 is perpendicular to x1 and points in the general direction of JC the third node defined x1 the x3 axis direction is determined by the right hand rule Le JB JA Sis perpendicular ta the plane of the element Version 12 5 1 8 4 12 06 STRAP The following figure shows a situation that can easily occur the x1 axes of the adjacent elements point in opposit
124. model geometry The current geometry for each model is stored in a binary file named GEOMnnn DAT where nnn indicates the model number However STRAP simultaneously creates an ASCII data file for each model named GEOINnnn DAT that contains the geometry data in the form of commands When the STRAP geometry file is corrupted the program may be able to recreate all or part of the file by reading the commands in the GEOINnnn DAT file Always backup the model before recovering the geometry In the event that the Recover is not successful please contact your STRAP dealer Version 12 5 1 3 8 12 06 STRAP 1 4 Setup Use this option to specify default values for colours units standard material properties output format etc Default values for STRAP program parameters are initially stored in the file STRAP INI located in the program directory Note that there is only one STRAP INI file for all users When a user revises a Setup parameter the program writes the new value in the Windows Registry Each user is allocated a separate section in the Registry so each user can create his own personal set of Setup parameters Note that the STHAP installation program does not write any Setup values in the Registry Colors Miscellaneous Print parameters Uebel i The program initially searches for default values in the Registry if it does not find a value i e the user has not revised the parameter in Setup it takes the default value
125. more details Wall elements Moment shear and axial force results for wall elements are always displayed relative to the wall local coordinate system The sign conventions are x1 y Ls top X24 X2 So bat xj Tren axis global 4 ai General case ib Special case x1 parallel to X3 X1 parallel ta height axis X1 parallel ta height axis Xd general X3 global direction 2 general X2 global direction xz righthand rule a righthand rule Version 12 5 1 8 7 12 06 STRAP Blank page Version 12 5 1 8 8 12 06 STRAP 1 9 General options 1 9 1 Step The R speed is called the Step and is the distance the gt moves on the screen each time the mouse is moved the minimum distance or an arrow key is pressed The current Step value is continuously displayed in the Data Options Area Mode definition All other modules F3 F4 There are three methods available for revising the Step Move the P into the Step text box Type in the correct value e Press to increase the Step or to decrease the Step e Click the buttons For node definition only Click the button to display a grid of dots on the screen the dots will be spaced at the current Step interval in both screen directions The jumps from dot to dot when the mouse is moved or when an arrow key is pressed To display the Grid automatically every time a node definition option is selected refer to 1 4 2 Setup M
126. n site rather than trying to arrange the bars around the opening Define dummy elements over the openings the area required will always be zero even if minimum reinforcement is requested Note that the dummy elements must be connected to all nodes on the opening perimeter fol ni Dummy elements are nat ERN connected to these nodes Right Wrong X Note in general the scale should be 1 50 If the drawing size is reduced e g 1 100 the text bars and dimensions will overlap and make reading the drawing very difficult It will probably be necessary to reduce the text size in such cases Version 12 5 8 9 12 06 STRAP kkk Blank page Version 12 5 8 10 12 06 STRAP 9 Bridge Postprocessor 9 1 Introduction Most bridge design codes require that each point on the bridge be designed for the arrangement and combination of loads that produce the most adverse moments shears etc at that point In order to comply with the requirements of the Code the bridge designer has to calculate influence lines for each result type at every point along the bridge Based on the results he then decides where to load the bridge It is obvious that as the bridge becomes more complicated the amount of work required increases enormously The STRAP bridge module calculates the load patterns and the corresponding results as follows The user defines a regular STRAP model of the bridge consisting of beams and or elements all l
127. nd element loads may also be defined relative to the global coordinate system standard load patterns may be stored in a file and recalled Each load case may be assigned to a different geometry stage All defined loads for the current load case are displayed graphically superimposed on the geometry Select one of the following options 2 2 D t i se amp CUT T B gx e EU m os Oy E in 8 p t im FE FE Version 12 5 To begin the definition of a new loading case To revise the loads in an existing load case To delete an existing load case Deactivated load cases are not solved but are not erased Automatically generate a series of moving load cases from a single basic case The global loads in the basic case will be offset by a constant increment in each successive generated case Automatically generate a series of load cases with alternating patterns of live load from basic load cases containing the dead and live loads on all spans The patterns are arranged according to Code requirements for calculating maximum and minimum moments in beams Calculate second order P D forces and moments Define wind load cases according to Code requirements Copy an entire load case Define sway unit load cases at specified nodes These load cases are required for the sway drift control option in the Steel postprocessor 3 1 12 06 STRAP 3 1 Joint loads Joint loads
128. ndrical system may be used for node coordinate definition Two types of reference systems are used in STRAP They are e the global coordinate system denoted by X1 X2 X3 uppercase e the local element coordinate system denoted by x1 x2 x3 lowercase STRAP uses right handed Cartesian reference frames xe j The X1 X2 and X3 axes or x1 x2 and x3 axes are perpendicular to each other and the positive direction of the axes are specified by the right hand rule Itis obvious that if the directions of any two of the axes are known then the direction of the third axis is easily determined mS y A THER In the following figure a beam element is located in space between nodes JA and JB The location of the nodes are defined according to the global coordinates i e their coordinates relative to the global axes X1 X2 X3 It is apparent the horizontal load P at node JB and the support reaction R at node JA should be referenced to the global coordinate system But it is difficult to define the distributed load w on the beam relative to the global axes and obviously a method is required to define the section orientation It is also apparent that results such as bending moments must be referenced to different directions for each beam Consequently the beam is provided with a local axis system x1 x2 x3 section orientation direction of loads CB eis and results are always relative to this local system Note that ea
129. ne of the global planes defined by three nodes the coordinates displayed in the Data Options Area are U V and W where The origin is located at the first node selected to define the working plane Uis measured from the first node in the direction of the second node The value of U is revised by moving the mouse horizontally V is measured perpendicular to U in the general direction of the third node The value of V is revised by moving the mouse vertically e Wis the dimension perpendicular to the plane Its positive direction is C Defined by 3 nodes determined by the right hand rule The value of W is revised in the Dialog Box at the bottom of the screen Note e the Working Plane option is in effect only for node definition e the program will automatically rotate the model if the working plane is perpendicular or nearly perpendicular to the screen when you enter the node definition option Version 12 5 2 8 12 06 STRAP Example Use a working plane to define node 41 on the sloped roof below The node location relative to the plane of the roof is Known as detailed in the figure but not relative to the global coordinate system v A2 i e define a Working plane as Defined by 3 nodes select nodes 10 20 and 30 in that order to create the Working Plane U V W as shown U 1 select Single node move the gt until U 5 0 and V 3 0 are 10 20 i displayed in the Data Options Dialog Box note that the mov
130. ng STATnnn DAT the program adds the load commands from the load cases of the second model to those of the first If you later decide to rerun the first model remember to erase the unnecessary load cases the load commands are required by the various post processors to calculate the span moment diagrams The process may be repeated to add additional models to the combined ones the models must be added in order of decreasing size largest to smallest Note Only the first model selected is revised 1 5 5 Recreate the model list Use this option to recreate a corrupted model list The model list is stored in the file ZZMODEL DIR each working directory has a different ZZMODEL DIR file This option scans the current directory to locate all model files GEOMnnn DAT STATnnn DAT etc and rebuilds the model list Note e the new model list file is named ZZMODEL NEW The corrupted ZZMODEL DIR file is not erased touse the new file copy it to ZZMODEL DIR 1 5 6 STAAD File Conversion This utility module converts STAAD input files to STRAP format Geometry loading and load combination commands are translated select Files in the Menu bar on the STRAP initial screen select Utilities in the pull down menu select Convert a STAAD input file to STRAP e type in the name of the STAAD file Note The program creates the STRAP GEOMnnn DAT STATnnn DAT and COMBnnn DAT files STAAD commands with syntax errors are not translated Error
131. nition the program will either automatically generate a separate combination for each load in the group or add the sum of the load cases in the group to the combination Examples Groups The following load combination is required 1 4 Dead 1 6 Imposed 1 6 Crane where there are 5 different load cases with Crane loads each corresponding to a different point of application of the load Instead of defining 5 separate combinations the 5 crane loading cases may be defined as a Group then only one combination which includes 1 6 Crane load group need be defined The program will then automatically generate a separate combination for each of the five loads in the group i e 1 4 Dead 1 6 Imposed 1 6 Crane 1 1 4 Dead 1 6 Imposed 1 6 Crane 2 etc Library Note that standard combinations need not be redefined in every model as combinations containing groups may be stored in the library For example 1 4 Dead 1 6 Live 1 2 Dead 1 2 Live 1 2 Wind elc For each Current Model retrieve the standard combinations from the Library then define groups that contain the dead live and wind load cases Version 12 5 5 2 12 06 STRAP ma Element Coordinate Systems The explanation of results for finite elements necessitates the introduction of two new coordinate systems in addition to the global and local element systems They are 5 2 1 Result Coordinate System X Y Z The result coordina
132. note that the ZIP files do not have to be created by STRAP but they must contain the directory file ZZMODEL DIR To retrieve a model from a ZIP file e select the ZIP file click and highlight one or more of the models in the list Copy from directory CAJUNKAVUccx ZIP Select model M amp A RUC Bentley Park Workshop Foundations NBR 6118 Deflections revised loads Version 12 5 1 3 6 12 06 STRAP e click Copy e select the files to extract Title Floor Plan with elements base Geometry file Iv Steel postp files Yreight tile Iv Loadings files J Concrete postp files Dynamic results M Stiffrress matis M Bridge lanes data hime history I Results files Bridge Result tiles cance e click Cop l 1 3 6 Display model file names The program automatically assigns file names to all files created for a model Use this option to display the file names for the highlighted model Version 12 5 1 3 7 12 06 STRAP 1 3 7 Add a file to model list The model list is maintained by the program and displays all models in the current directory both those created by the user by running STRAP in the directory or those copied to the directory using the program Copy to and Copy from options Note that the model list is stored in the file ZZMODEL DIR this file is found in every working directory and backup diskette Models whose files are manually copied e g using DOS Copy command to the current
133. ns P Command ior geometry and load definition options only This button is displayed only when there is a corresponding Command Mode for the currently displayed topic Clicking the button will display an explanation on the command format 1 9 6 Icon bar The icon bar provides a shortcut method for accessing STRAP options Each icon on the bar represents a different option Click the icon once to run the option Hold the R on the icon for several seconds to display the option description For example dit oom Rotate Display Draw IBID 2 a7 me Note that you can create new icon bars or customize existing bars Refer to 1 4 4 Setup icon bars 1 9 7 Undo Clicking the Undo option in the menu bar automatically cancels the last definition the graphic display is immediately redrawn Note that Undo may be pressed repeatedly but will only cancel commands from the current session Version 12 5 1 9 5 12 06 STRAP 1 9 8 Print tables The following menu appears when you request to print tables directly to the printer or to a file General options EmA hd techs oe ha iei p Refer to 1 9 9 Print drawing Print style Medium quality First page no o Date Send output to a file Send output to a Word file OK Cancel Word format file The tables may be saved in an MS Word RTF format file Rich Text Format and may be imported into any wordprocessor or program that recognizes this format opecify
134. ns Walls The capacity is calculated separately for each segment in the wall determination of the critical STRAP load combination calculation of magnified additional moments for about the weak axis and minimum moments selection of reinforcement arrangement which is able to withstand applied bending moments and axial force for all load combinations subject to minimum Code requirements The reinforcement is distributed equally on both wall faces Revise parameters properties etc and compute again Create column drawings and tables Print results Version 12 5 8 5 12 06 STRAP 8 4 2 Design procedure seismic The design procedure is more rigorous for models designed for seismic loads General Define all continuous beams columns including support locations and support widths Define all properties not specified in STRAP geometry by dimensions e Specify the default parameters for all beams columns In particular specify the seismic frame type and identify the seismic load cases click the 9smie tab Define parameters for specific beams columns if different than the default parameters Seismic The Codes specify the following hierarchy for the calculation e beam longitudinal reinforcement is calculated from the design forces but not less than the minimum specified by the Code beam shear reinforcement is calculated from shear forces derived from the moment capacity of the beam based on the
135. nstructed to check the suitability of a section specified by the user The program automatically searches for the critical load combination and checks the section for bending moments lateral torsional buckling shear axial forces and combined stresses as well as deflections and slenderness The program may be instructed to select sections according to the methods outlined in any one of the following structural steel design codes For more information on the Design Assumption refer to British Standard BS 5950 Part 1 2000 Structural Use of Steelwork in Buildings Part 3 Section 3 1 Design of Simple and Continuous Composite Beams Eurocode Eurocode 3 Design of Steel Structures Part 1 1992 Eurocode 4 Design of Composite Steel and Concrete Structures Part 1 1990 AISC Load and Resistance Factor Design 1993 AISC Allowable Stress Design 1989 CSA CAN 16 1 Limit States Design of Steel Structures 1994 AASHTO LRFD Bridge Design Specifications 1999 AASHTO Standard Specifications for Highway Bridges ASD 1996 SABS 0162 1 1993 IS 800 Code of Practice for General Construction in Steel 1984 2003 LRFD e GBJ 17 88 Specification for the Design of Steel Structures 1988 Cold formed AISI Specification for the Design of Cold Formed Steel Structural Members 1986 Edition with 1989 Addendum ASD only 1999 Edition ASD and LRFD e CSA S136 94 e Eurocode 3 Part 1 3 1996 The
136. nto STRAP geometry Note that the program does not check whether the defined cables actually lie within the section Calculation of losses and deflections are calculated at various times stages for each beam measured from the day the beam is cast All dates casting and stages are measured from an arbitrary zero date referred to as the start of construction For a specific beam 10 2 How to use the program POSTTEN is a STRAP postprocessor program that designs post tensioned beams and slabs in solved STRAP models The STRAP model must be defined as follows Define load cases with all loads but without prestressing loads e Solve the model e Define load combinations in the results module Select the Files Post tension option To design post tensioned beams and slabs e Specify the design parameters e g concrete type prestress loss parameters etc Define a Stage table for models where not all of the cables or beams are prestressed at the same time The stages are named and defined by the number of days from the start of construction Define all of the beams to be prestressed by selecting the start and end STRAP member Define all of the slabs to be prestressed by specifying the start and end nodes of prestressing lines that pass through the relevant elements Each line is designed similarly to a beam i e all cables are parallel to the line Note that the lines do not have to be parallel to element boundaries e Ex
137. oad cases self weight wind earthquake etc other than highway vehicle loads and solves the model for these loads e The user then selects the Bridge design option and defines the following lanes lane loads load cases The program then calculates for every point in the model and for every result type moment shear etc the combination of uniform vehicle and knife edge loads that give the maximum and minimum result at the point The calculation is carried out according to user specified parameters such as the number of lanes that may be loaded simultaneously the uniform load intensity for various lengths of load etc The user can then append load cases to the STRAP results file containing maximum minimum results at each point In addition the user can select any point on the bridge and generate an influence line at that point for any result type Both the influence lines and the corresponding load arrangement may be displayed graphically The basis of the calculation is the division of each lane into a series of strips The width of each strip perpendicular to the axis of the lane is equal to the width of the lane and the length of the strip parallel to the axis of the lane is specified by the user The program loads and solves each strip with a uniform unit load and calculates the influence lines and the critical load arrangements from the results Similar to finite element analysis the accuracy will increase as the
138. odel naturally consisting of beam elements e g a skeletal frame structure is analyzed by STRAP the results will be identical to those calculated manually using any exact method Similarly the method of creating the STRAP model for such structures is usually obvious each beam or column is represented by a single beam element e Finite Elements Finite elements are two dimensional elements that are used to model surfaces such as plates shells and walls They may be either triangular or quadrilateral in shape Finite elements on the other hand give inherently inaccurate results the degree of inaccuracy is usually acceptable by most engineering standards for the following reasons The elements should be connected along their common boundaries but in the finite element model they are connected only at their common nodes Thus there is a relaxation of continuity along the boundary although the mathematical development of the elements ensures satisfaction of some but not all of the boundary continuity requirements The mathematical development of the elements assumes a linear stress distribution through the element In reality the distribution is usually more parabolic In a continuum structure such as a flat plate there is no natural subdivision of elements so the structure has to be artificially divided It is obvious that as the continuum is divided into a finer mesh smaller elements the degree of discontinuity is lessened
139. of the natural frequencies of modes i and j the constant modal damping Application of the SRSS method generally provides an acceptable estimation of the total maximum response However when some of the modes are closely spaced the method may grossly underestimate or overestimate the maximum response Large errors have been found in particular in space models in which the torsional effects are significant The term closely spaced may be arbitrarily defined as the case where the difference between two natural frequencies is less than 10 of the smaller frequency The CQC method is a more precise method of combining the maximum values of modal response Note that the two methods are identical for undamped models 0 The program also calculates e Mass center and rigidity centre of each level e Maximum minimum deflections at each level and the story drift For additional theoretical explanations and background refer to any textbook covering dynamic response of multi degree of freedom systems Version 12 5 6 2 12 06 STRAP 6 3 Forced Vibrations and Time History Response This module calculates the transient history response of a model subject to dynamic loads in which viscous damping is present It enables the dynamic analysis of models subject to impact impulse or cyclic loads or any other type of load that varies with time The equations of motion are solved on the basis of the results from the Natural Frequency and Mode Sha
140. ogram To print the full User s Manual refer to Appendix A2 Detailed explanations on all of the options and features are available in the on line Help supplied with the program To display the entire User s Manual select the Help option in the program menu bar To display Help for the current option press F1 For more information on Help refer to section 1 9 5 STRAP STRuctural Analysis Programs is a package of computer programs for the analysis of linear elastic structural models The system includes static analysis and dynamic response analysis STRAP programs offer the engineer an easy to use tool for analysing a wide range of frame and truss structures continuum mechanics problems plates shells etc or a combination of both types Frame structures consist of an assemblage of one dimensional beam elements defined by the cross section properties Continuum mechanics problems are solved using the finite element method the structure is modeled by two or three dimensional area elements interconnected only at nodal points The behaviour of a finite element model closely approximates the behaviour of the real structure STRAP includes the following elements e One dimensional Beam element Two dimensional Quadrilateral element Triangular element e Three dimensional Solid element The program allows elements of all types to be defined in the same model This is very useful when analyzing structures such as plates w
141. onstant torsional moment of inertia and torsional flexural buckling constant Solid sections Sections formed by a closed contour For example 130 Define the To create closed the solid contour sections 320 245 Several separate contours may be defined to form a section the additional contours may be specified to be holes The properties may be copied to the STRAP geometry Standard solid shapes may be defined by entering the dimensions parametric section library Solid shapes may be imported from a DXF file Properties calculated include Torsional moment of inertia Version 12 5 12 1 12 06 STRAP 12 2 How to use the program e Select New line section or New solid section in the Sections menu in the menu bar New line section define a series of connected segments to form the section New solid section define a closed contour to form the section e Add subsections if necessary to create more complex sections For example New line section define a series of connected steel sections to form light gauge steel sections The subsections are defined separately and must be connected New solid section define a hole in the first contour e Select Display properties in the Output menu in the menu bar to display the computed section properties A I J centre of gravity etc and Print section to print the results Transfer the properties of the current section to STRAP geometry select Copy to cli
142. or 100 10x10 0 30 64 8x8 0 50 36 6x6 0 90 16 4x4 2 00 4 2x2 6 20 There is no obvious advantage gained from defining the model with more than 36 elements Example 2 Consider the three shear wall structures in Figures a to c The walls are identical except for the size of the openings Figures d to f show three possible computer models for the corresponding shear walls a rough mesh has been used for clarity e model a has relatively narrow walls and beams and so can be modeled entirely by beam elements as shown in d Note the rigid offsets in the lintel beams e model b has wide walls and shallow beams H H and so can be modeled by the combination of finite elements and beam elements as shown in e The lintel beams are extended into the wall for continuity OT e model c has wide walls and deep beams and should be modeled entirely by finite elements as shown in f d e It is important to stress the following points e all of the models are inaccurate to some degree Model a uses beam elements to model the wall Model b and c use finite elements and so the degree of accuracy is dependent on the number of elements used see below e there is no sharp boundary between beams that are considered deep or shallow i e it will not always be obvious which model is the most appropriate e As opposed to example a there are no exact solutions available that the compute
143. or triangular elements 3 and 7 will not be relative to the same axes as quad elements 1 2 4 5 6 Slab reinforcement Confusion will result in the reinforcement calculation if the local x3 axis directions are not consistent The program assumes that the TOP face is the Z face of the slab and the BOTTOM face is the Z face Hence Top and Bottom reinforcement in elements may actually be at the same face if their x3 axis directions are reversed Version 12 5 5 4 12 06 STRAP Local axes of a selected element The result axes for an element may be defined as identical to the local axes of a different element The different element must lie on a parallel plane For example local axes were specified for a group of elements but their local x3 axes directions are not consistent Confusion will result in the reinforcement calculation because the program assumes that the TOP face is the Z face of the slab and the BOTTOM face is the Z face Hence Top and Bottom reinforcement in different elements will actually be at the same face To unify the results specify that the results axes for all elements are identical to the local axes of one element 5 2 2 Reinforcement coordinate system The reinforcement coordinate system is required for reinforcement design moment calculation in concrete slab models The reinforcement axes X and Y are defined as parallel to the directions of the reinforcement The program assumes that X is al
144. ot less than the design forces e column longitudinal reinforcement is calculated from the design forces but may be increased to ensure that the sum of the column moment capacities at a joint exceeds the sum of the beam moment capacities e column shear reinforcement is calculated from shear forces derived from the moment capacity of the beams connected to the ends of the columns but not less than the design forces This method ensures a hierarchy of strengths of the different members Note that three different moment capacities are calculated by the program e factored normal capacity for non seismic members nominal capacity calculated using concrete and steel strengths not reduced by Code factors e probable capacity calculated using increased steel strength i e actual conditions and each calculation uses the appropriate capacity The design of both longitudinal and transverse reinforcement in columns is dependent on the capacity of the beams Therefore it is mandatory to compute the beams prior to computing the columns Version 12 5 8 2 12 06 STRAP 8 3 1 Beams Moment The beams are designed for all load combinations as defined by the user In addition the program complies with the following requirements found in all Codes e at support the positive moment capacity is not less than a specified percentage of the negative moment capacity e at any point along the beam the positive and negative moment capacity is not l
145. ow the line as follows stresses compression stresses are negative and are drawn below the line e moments moments are positive if they create compression stresses above the element and are drawn below the line left above The above side is always to the left of the line when looking in its positive direction i t 4 The positive direction is determined as follows right below e line parallel to a global axis within 5 of the axis the positive direction of the axis e plane model line defined by 2 points from the 1st point to the 2nd point Space model general case in the general direction of X1 except if perpendicular to X1 in the general direction of X2 if perpendicular to X1 X2 in the general direction of X3 Note that while the stress distribution within each element Tg Te Exact bending is assumed linear the actual stress distribution is usually from proaram moment diagram non linear This discrepancy results in discontinuities in the result diagram as shown below Using a finer mesh in areas where the slope of the result diagram varies significantly will improve the accuracy of the results An indication of the inaccuracy can be obtained by comparing results at the same node for adjacent elements theoretically they should be identical but in general they differ l Sl Discontinuity in plotted moment diagram Version 12 5 5 7 12 06 STRAP 5 3 4 Deflections
146. pand the combination table specify the Permanent loads in the combinations for the calculation of deflections and time losses assign each load case to specified stage if relevant Note that a load case may either be applied or removed at a stage Version 12 5 10 1 12 06 STRAP For each beam Specify the type and number of cables and the prestressing force The program displays a Magnel diagram as a design aid for the selection of the prestressing refer to 10 3 How to define cables Specify the trajectory of the cables The program displays the upper and lower permissible cable boundary lines superimposed on the beam elevation assign selected cables to different stages if relevant select Solve the program creates cable force load cases at each of the defined stages and time steps including losses at each step and solves the model for these cases The new load cases and their results may be viewed in STHAP Revise the cable details and trajectory if necessary Display print tables of stresses deflections shear and ultimate moments for each beam If the prestressing is done on several distinct model stages that represent intermediate stages of construction the stages must be defined in STRAP geometry These STRAP stages are then assigned to the relevant design stages in the POSTTEN module For example Geometry Loads self wt of RAP stage 1 STRAP stage 2 STRAP stage 1 STRAP stage 2 L1 L3 L2 of RAP
147. pboard in the Output menu in the menu bar For line sections only Create a table of cold formed sections for the STRAP properties table The table is created from a Line section by defining sections with similar shapes but with different dimensions Select Create table in the Section table menu in the menu bar select an existing Line section and enter a table of dimensions for the shape select Transfer to STRAP in the Section table menu in the menu bar to copy all section in the table to the STRAP property files as cold formed sections 12 3 Hints and suggestions For separated back to back channels angles etc connect the two channels with a subsection having the correct length and a thickness 0 01 Example a e For connected back to back channels etc where the slenderness of the web must be calculated using the combined web thickness define the web as a subsection with the double thickness and the flanges by four subsections connected to the corners of the web Example b e For connected back to back channels etc where the slenderness of the web must be calculated using the web thickness of a single channel define the second channel as a subsection and connect at one point Example c To compute Define t 0 01 a L 0 014 h pu far slenderness p x id for slendernes Version 12 5 12 2 12 06 STRAP Al Hardware Requirements and Program Capacity Minimum Hardware hard disk with 35 mb of free space
148. pe analysis The equations of motion are md Cc kHx P F t diagonal mass matrix matrix of damping coefficients stiffness matrix joint load distribution time history of the applied forces A uH Hn W dH I The program assumes e At each node the history behaviour of the load is represented by the input joint loads multiplied by the history function F t e the history function F t is composed of either A series of straight line segments defined by a set of pairs of time and amplitude values t1 F t1 t2 F t2 tn F tn where tn gt tn 1 gt 0 a sine function curve A different history function may be defined for each load case e the damping matrix c is proportional to the mass matrix c 2 m where is a constant diagonal matrix The damping is defined as a set of coefficients one for each mode shape where the coefficients represent a percentage of the critical damping cr wn wn modal frequency Version 12 5 6 3 12 06 STRAP Blank page Version 12 5 6 4 12 06 STRAP 7 Structural Steel Design 7 1 Steel Design General The STRAP Steel design module is a program for the design of structural steel buildings The program selects for each member the lightest section which meets the Code requirements The sections are chosen from a specified table Section constraints design data and intermediate supports may be defined Alternatively the program may be i
149. program strives to design the lightest structure possible the section chosen is the one with the least self weight that satisfies all of the design criteria for all loading combinations and meets the Code requirements For all Limit States Codes all Codes except AISC AASHTO AISI ASD and 18 800 The factored combinations may be defined in STRAP loading or in the Combinations option after the solution The choice does not affect any of the design calculations except for deflections which are based on service loads The module assumes that CASES are unfactored i e the combinations were defined after the solution If the factored combinations were defined in Loading the deflection results for the load cases will also be factored The allowable deflection limit should then be increased proportionally Version 12 5 7 1 12 06 STRAP 7 2 Steel section tables and selection The program contains several complete section tables the master table British sections CONSTRADO tables e Canadian American sections ASTM e South African e European sections Euronorm e Indian Cold formed sections may be added to the master tables In addition e A user steel table may be created This table can contain sections from any or all of the three tables above or user defined rolled cold formed sections Refer to 1 5 2 User steel table for instructions e additional built up sections may be defined by specifying dimensions the program
150. py a model from another directory or to restore a model from a floppy diskette Note that multiple models may be selected To copy the models e type the drive directory in the Copy from directory box select a directory using the _Tree option or click button hell to choose a recently selected directory press Enter or click the e select the model or models to be copied Copy from directory JA amp C381 Tree Select model Laboratory building seism seisme seism3 Cancel to select more than one model press the Ctrl key when clicking on the additional models e for each model selected specify the files to be copied from the list displayed only files that are marked with a M will be copied Click on the file description to toggle the status Click the _ Copy button to begin copying Note e if the model was copied to two or more diskettes the program will instruct you change diskettes e to create a copy of a model in the current directory refer to Make a copy of a model 1 3 2 2 1 3 3 Change current directory The current directory is displayed at the top of the screen Change current directory Enter new directory name pO OK ree Cancel to select an existing disk directory on any drive type in the name of the path or click the Tree button and select the path in the standard Windows Select a directory dialog box Tocreate a new directory click the Tree button and
151. quired for design are allowable maximum deflection allowable maximum slenderness tension and compression beam end support conditions e column effective length factors Section orientation Steel grade Additional design constraints for section selection may also be specified e minimum and or maximum section dimensions for each member aseries of members may be defined as identical i e the same section will be selected for all members in the series Version 12 5 7 3 12 06 STRAP 7 4 Compute When the option Compute is selected in the Main Menu the program begins automatic member selection The progress of the design is displayed on the screen Steel member selection Now designing member 15 Now checking section l fxfbxl3 UB The program begins the design by checking the lightest section available If the check fails because of inadequate capacity or failure to meet user defined constraints the program selects the next heaviest member in the list and begins the check again The process is continued until an adequate section is found Note if the type assigned to a member in the Section option is a cold formed section the program automatically designs the member according to the specified cold formed Code If more than one type is allowed i e if there is more than one type in a group the program searches for an adequate section independently for all of the types and then selects
152. r results can be compared to Therefore good engineering judgment is required to select the correct model In summary e the model selected must represent the actual structural behavior of the structure accuracy increases as the number of elements increases but both solution time and file size also increase Thus the selection of the model and the division of the model into elements is often a tradeoff between e more exact modeling of the structure vs general simplicity of the model e increased accuracy vs reduced solution time and file size Version 12 5 1 7 2 12 06 STRAP The following are guidelines for constructing an accurate finite element model Use quadrilateral elements In general try to use quadrilateral elements instead of triangular elements as they give more accurate results Remember that the four corners of a quadrilateral element should all lie on the same plane If this is not possible use two triangular elements in place of each quadrilateral Element shape Quadrilateral Elements The greatest accuracy is achieved with a square 1 1 element Elements with a base height ratio up to 1 2 give good results but elements with a ratio of 1 5 will be unreliable Try to use rectangular shaped elements whenever possible If not the internal angles should not vary greatly from 90 Angles of 30 or 150 will greatly reduce accuracy Elements with convex angles should never be used Triangular Elemen
153. ry as defined in STRAP does not provide sufficient information for the Code to carry out an accurate design For example Figure a shows a typical steel floor plan Figure b shows the same floor as analyzed in STRAP It is obvious that the program is unable to determine which STRAP members form continuous beams i e which chains of members must be designed as a single unit by the program For example members 21 22 23 24 25 50 form a single beam ot 25 23 34 258 S M MMG presi o o l l o o Q 0 0 0 n0 o I I o o a b Another important item that must be defined in the module is the location of intermediate supports The support locations are required by the program in order to automatically determine the unsupported length for beams and the design length for columns Concrete slab e beam a has a continuous support on its upper flange and is unsupported along the entire bottom flange e beam b has a single support on its upper and lower flanges beam c is unsupported on its upper flange and has a ibj single support on its lower flange If the upper flange is entirely in compression the section required for each of the beams a b c will be different As the support data is not available from the STRAP eX geometry it must be defined in this module Similarly column e has an unsupported length about its minor axis double that of column d Other data items re
154. s Singularity or near singularity detected at node ___ The program will take corrective action i e supply missing restraints in order to proceed with the solution Version 12 5 4 3 12 06 STRAP Note that the program arbitrarily restrains the first joint in the model that will make the model stable The corrected model usually does not correspond to the model that you intended to solve check the reactions in the result table to see if the program created new supports or display graphic displacements and check if the deflected structure has the correct form If the model is not as intended ignore the results and return to geometry to revise the input Note e this singularity message may be displayed when there is a large difference between maximum and minimum moment of inertia values defined for property groups 4 4 Problems General e Ifthe solution is interrupted by a power failure or computer malfunction the solution may be restarted from the point of the last backup as explained in Solution time backup Warning messages solution will be completed ifthe model consists of two or more unconnected parts if two or more beams connect the same two nodes too many beams connected to one node node element optimization is discontinued Error messages solution is aborted Total number of degrees of freedom exceeds 192 000 32 000 x 6 Various errors in the geometry Not enough space on disk At the star
155. s Results general Made results The following print options were selected GEOMETRY nodes restraints properties beams elements springs LOADS None RESULTS sorted by loads maximum of displayed beams display all load cases Nodes deflections Beams end results Elements Mone 1 3 2 File management 1 8 2 1 Delete This option deletes an entire model from the list or erases selected files only e g loads results etc Note that multiple models may be selected To delete models or files click and highlight model names in the list to select more than one model press the Ctrl key when clicking on the additional models ifyou selected multiple models Multiple delete More then one model is selected amp Delete the models one by one C Delete all models without prompting Cancel Delete models one by one the following menu will be displayed for each model selected Delete all models without prompting the following menu will be displayed only once and the selection will be used for all models Version 12 5 1 3 2 12 06 STRAP e select the files to be deleted Delete files for model End Shear Vall M Geometry file teelpustpzfiles M eihtdile Iv Loadings files W Concrete postp files Dynamic results Stiffrress matrix T Bridge lanes data F Time history M Results files Bridge Besultfiles OK Cancel only files that are marked with a I will be copie
156. s the only option available for plane frames contour area defined by nodes selected beams wind load T applied az linear beam load Global vind load applied as b joint beam element load e as uniform beam loads on a lattice structure the program assumes that the model is an open structure i e the wind blows through the model This option is primarily intended for transmission towers open trusses in industrial buildings etc wind d uniform load applied to beam in model The program calculates the projected surface area of each member perpendicular to the wind direction calculates the wind load for individual members in a lattice structure according to the Code and applies it to the selected beams Version 12 5 3 4 12 06 STRAP 4 Solve the model 4 1 Solve general Refer to Solution method 4 2 for a detailed explanation on the method used by the program to solve the model The program deletes the inverted stiffness matrix at the end of the solution phase in order to save disk space However for large models it may be advisable to save the stiffness matrix if the same geometry will be solved with different loads the solution will then skip the matrix inversion Do you want to save the matris For this madel Press to save the matrix At the start of the solution the program displays the header STRAP matrix solver Mi EX Abort HATRI ASSEMBLY AND DECOMPOSITION STAGE e Original
157. section shape and name may be imposed on the beam line using one of the following four methods LUB254xz146x37 UB254z146x37 Version 12 5 7 4 12 06 STRAP Note e the drawing may be generated on any plane e g plans or elevations If more than one plane is displayed on the screen when this option is selected the program will prompt the user to select a plane defined by three nodes e the program writes the section name adjacent to each member The name is written only once for a string of identical sections The text size is specified by the user e The program differentiates between primary and secondary beams and terminates the line of the secondary beams before the intersection with the primary beams Version 12 5 7 5 12 06 STRAP Blank page Version 12 5 7 6 12 06 STRAP 7 6 Example Design the plane frame shown below Note This example illustrates the method of application of several steel design options The example is intended as an aid to learning the proper use of the program options and is not intended as a guide to proper engineering judgment in the construction of a model for design DezdilImpaosed 20 40 E35 20 40 Lives 5 Concrete 20 40 2040 20 40 slab typ 7 D Iz12 25 D Iz12 25 LTITTTTIITTTIITIIITITTITTD 2 D 40 55 anve5 12 me T ZONA Load cases 1 Dead 2 Live imposed 3 WWind Call horiz Load combinations for AlISC ASD 1 1 40 1 6L 1 1 00
158. stage 3 earRAP stage 3 Cables Assigned to Assigned to stage 1 Stage 2 Assigned to Stage 3 STRAP Create the separate stages then define the loads for each stage without prestressing loads in a separate load case and assign it to the relevant stage solve the model Note that each load is defined only once at the stage where it is first applied This is illustrated by the self weight loads in the example above the self wt of the cantilevers are applied only in Stage 1 and 2 even though they continue to act in Stage 3 Define load combinations in the STRAP results module These combinations should represent the loads acting at each stage for example C1 L1 C2 L2 C3 L1 L2 L3 POSTTEN Assign the relevant STRAP stage to each POSTTEN stage in the Stages stages option Assign the combinations to the relevant stages in the Stages Load table option Define the cable assign each cable to the relevant stage in the Design losses jacking sequence option as shown above Version 12 5 10 2 12 06 STRAP 10 3 How to define cables d e select cable e define cables each may contain more than one strand so the total force lies within the Magnel diagrams For example ue No of Strand Start End X of Total strands type iens Qu jacking p o 3 STRANDS o m 2 J gt HISTRANDS Eigp qq E aeaa Total force of all cables 3323 67 p p 5674 3612 J674 3051 m 2314 2314 1360 1360 1271 10 661
159. t limit by type The program differentiates between the different text types on the drawing and allows the user to select texts of a certain type s only For example if you want to change the color of all beam numbers Nodes Beams Set Nodes and Frames titles to No Frame Titles 4a ad click OK Version 12 5 1 9 9 12 06 STRAP New lines Add a new line to the drawing Specify the location of the line start and the line attributes Definition f Bycursor The line may start at any location on the Line end drawing or at the start end of an existing line Direction Any C Horizontal Vertical Draw the line in any direction or draw only the harizantal vertical projection of the line ta the end point width 0 Specify the line width 0 1 pixel color 1 Select the line colour fram the colour palette Specify the line type Move the R to the location of the line start or highlight an existing line start end and click the mouse e Specify the location of the line end Note that the start and end of the line may be defined using different options in the menu above e Continue to define segments using the end of the previous line as the start of the next line or double click the mouse to stop 1 9 41 Entities Selection 1 9 11 1 Node Selection Many options include instructions to select one or more nodes NODE SELECTION select by window select by polygon Can
160. t X1 X2 X3 respectively For the positive direction of the moment refer to 5 4 1 Sign conventions The results displayed are in effect the actions on the support Results Sorted by Loads The program prints the sums only for the non zero nodes In effect the sums are the reactions at the restrained nodes note that they are actually the actions on the support For example MODE A Xe X3 Ad XB xB 2 591 49 896 000 000 000 000 1 110 58 305 000 000 000 000 464 31 546 000 000 000 000 093 24 966 000 000 000 000 AV 22 795 000 000 000 000 he 12 553 000 000 000 000 em cl c2 M l SU 000 200 000 000 Ut 000 000 The sum of the reactions displayed in the bottom line should equal the sum of the loads which were applied in that loading case Due to the limited numerical precision of computers and particularly micro computers non zero values will occasionally appear in the Reactions for unrestrained degree of freedoms i e nodes that were not defined as supports Usually these values will be negligible in comparison to the internal forces at these degree of freedoms approximately N 10E 5 where N are the internal forces at a DOF However in certain instances the numbers could be much greater In such cases the user should check for the following causes Singularity messages during the solution stage Too large a difference between the values of the largest and smallest moment of inertia
161. t more than one model press the Ctrl key when clicking on the additional models if you selected multiple models Multiple copy Ea More then one model is selected amp Copy the models one by one C Copy all models without prompting Cancel i Copy models one by one the following menu will be displayed for each model selected i Copy all models without prompting the following menu will be displayed only once and the selection will be used for all models select the files to be copied Copy to D strap1 Tree i Title Space frame M Geometry file Steel postp files Mfengiit tile I Loadings files Iv Concrete postp files Dynamic results Stiffrress matrix M Bridge lanes data ime history M Results files Bridge Besultfiles cance choose a recently selected directory press Enter or click the Revise the Title optional only files that are marked with a M will be copied Click on the file description to toggle the status Copy press the button to begin copying Note when copying multiple or large models to a diskette the program displays a message with the number of additional diskettes required and notifies when to change diskettes All diskettes must be formatted prior to the backup To create a copy of a model in the Current directory refer to 1 3 2 2 Make a copy of a model Version 12 5 1 3 4 12 06 STRAP 1 3 2 4 Copy from another directory Use this option to co
162. t of the solution the program checks if sufficient disk space is available to complete the calculations If not the program displays a warning message and lists the number of bytes required Erase unnecessary files from your disk and restart the solution Version 12 5 4 4 12 06 STRAP 5 Results The program enters the output module of the program after completing the solution F x ptions Combinations Punching Slabs Help To display graphic tabular results i i E e ee E e Define the load Combinations menu bar Refer to 5 1 4 Bridge E Postten C Draw E e Specify Options e g result axes menu bar Refer to 5 2 x Select Tables or Draw or Single beam C Tables e Click C Single 2 beam Treen to display the tabular graphic results geom only Gu to print the tabular graphic results Refer to 1 9 8 print and 1 9 9 for standard print options MICI geom only redraw the current screen with geometry only and without results This option is convenient when rotating large models with results that take a considerable amount of time to calculate and draw e g contour maps The program must recalculate the results every time one of the rotate icon is clicked In such cases select geom only rotate the model without the results then select Draw to redisplay the results Note e Results from several different models can be combined prior to displaying the results Refer to
163. tally will increase the bandwidth size However the user need not worry about the numbering method The program automatically renumbers the model so that the bandwidth has the minimum width and so minimizes the solution time The renumbering is internal so the results always appear according to the defined node and element numbers The program begins the solution by inverting the stiffness matrix The stiffness matrix is a function of the geometry only and the inversion of the matrix takes up the majority of the solution time If the program finds a zero value along the diagonal when building the stiffness matrix the program replaces it with the value 1 0E 20 and displays a ZERO STIFFNESS warning The program decomposes the matrix by the CHOLESKY method Version 12 5 4 2 12 06 STRAP During the decomposition of the matrix if the program discovers a value X along the diagonal that after decomposition has a value 1 0E 9 X the program replaces it with the value 1 0E 7 X and displays a SINGULARITY message Beam Elements The program includes the shear contribution in the beam stiffness matrix and allows for a reduced shear area Triangular Elements e Bending The program uses the HSM element Hybrid Stress Model as described in A Study of 3 Node Triangular Plate Bending Elements Jean Louis Batos International Jour for Numerical Methods in Engineering Vol 15 1771 1812 1980 Plane Stresses The program uses a constant strain pl
164. te system is the set of axes about which the element results are calculated and displayed In most cases the results axes are identical to the local or global systems If the direction of the local x1 x2 axes for all of the elements are not co directional there will be an apparent inconsistency in the results and this will lead to time consuming Mohr s circle calculations The program automatically assigns a default result coordinate system to each element In general the default X axis is as close as possible to the general direction of X1 The default result X and Y axes are determined as follows Plane frame plane grid The X axis is always parallel to the global X1 axis and the Y axis is always parallel to the global X2 axis If the program discovers that the direction of the local x3 axis of an element is opposite to the direction of the global X3 axis it reverses the sign of results for that element This insures continuity of the lines e Space frames Elements parallel to the X1 X2 global plane X X1 Y2X2 Z X83 Elements parallel to the X1 X3 global plane X X1 Y X3 Z X2 Elements parallel to the X2 X3 global plane X2X2 Y2X3 Z 2Xl1 Elements not parallel to a global plane e X direction parallel to the line of intersection of the element plane with a plane parallel to the X1 X3 global axis X in the general direction of X1 e Y perpendicular to X and in the general direction of X3 Y in the direction of X2
165. ted in ascending order e g sorted by model title models starting with A are displayed first sorted by date the oldest model is displayed first Click again to sort in descending order the symbol in the header will be revised to The small icon displays the current status of the model HA only geometry has been defined Fed geometry and loads have been defined Fd the model has been solved results may be displayed dynamic mode shapes have been calculated ina static loads have been defined To create amend a model Define a new model referto 1 2 1 e Amend rerun an existing model refer to 1 2 2 Version 12 5 1 2 1 12 06 STRAP The following options are available in the toolbar Files Solve Setup Utilities Df Help e Files pull down menu referto 1 3 e Setup referto 1 4 e Utilities refer to 1 5 e DXF import export options refer to 1 6 Note The program stores data for each model in a series of files All file names for a particular model include a number assigned by the program when the model is created For example if the number displayed is 017 then the model files are GEOM017 DAT geometry STATO17 DAT loads RESLTO17 DAT results ete File management is handled by the program and this number is displayed for information only corrupted model lists may be restored by using the Files Utilities Recreate a models list option Refer to 1 5 5 1 2 1 Define a new model s
166. the model the wall cross section is defined first and then is attached to the model by selecting a vertical line of nodes the program automatically creates any additional nodes that are required each wall section may consist of multiple segments together with coupling beams for example Wall 4 segments s1 s4x 57 23 s4 i 7 A A I2 i A Coupling beams the number of segments is unlimited the arrangement and orientation of the segments is not restricted and each segment may have a different width coupling beams may have varying heights For example i Reference point J each wall has a reference point at the end of one segment This point is used to attach the wall to nodes in the model referred to as the Attachment nodes when the wall is attached to the model the program generates a series of rectangular elements from the segments and creates the necessary nodes at the corners Example the following wall is defined and attached to the model The wall is attached to the nodes atits reference Point according to a default orientation Fa 4 e Reference point Rotate the wall about the reference point to its correct alignment The program creates 6 rectangular elements e1 eb and 8 new nodes im d ngj Version 12 5 2 18 12 06 STRAP Wall Each coupling beam generates three beams in the model the coupling beam itself and a beam in each of the adjacent walls that
167. the model will be selected Note beams elements not displayed because of the Zoom option will be selected beams elements not displayed because of the Remove beams elements option will not be selected Select beams elements with i One node in the window polygon all elements with at least one end corner node in the window polygon will be selected gt Both nodes in the window polygon only elements with all end corner nodes in the window polygon will be selected Examples Elements selected All nodes na elements Al nodes elements 1 and 2 One node all elements One node all elements Select only beams elements parallel to a beam elements You may impose a further limit that the beams elements selected will be only those parallel to a specified one This option allows you for example to define a window around an entire frame but to select only the beams or columns Version 12 5 1 9 14 12 06 STRAP Multiple selection Turn on the checkbox if you want to define several windows polygons or lists for the same command After every window etc the following menu is displayed Add more beams to selection Hemove beams trom selection End selection Continue without selecting more elements Add more beams Define another window polygon etc for the same command Delete beams Delete members from the list window etc already defined for this command Limit by properties Further limit the beam
168. the positive direction is from the start node JA in the geometry tables to the end node JB x2 As x1 and x8 are known x2 is determined from Always parallel to the global X2 axis the right hand rule x3 Always parallel to the global X3 axis As x1 and x2 are known x3is determined from the right hand rule If the angle between the local x1 and the global X3 axes is greater than 0 006 the axes are assumed NOT parallel As angle of this magnitude can result from computer inaccuracy the local x3 axis direction of all beams parallel to X3 should be specifically defined Examples EN User defined local axis directions As explained above the program automatically defines default local axis directions for each beam STRAP always assumes that the major minor beam axes are parallel to the local x2 x3 axes i e the properties of all beams are defined relative to the local coordinate system It is apparent from the example in the figure below that the beam section can be oriented in an infinite number of angles about the x1 beam axis and so the default local axes directions may not be correct The beam in Figure a below lies on the X1 X2 global plane by default its local x3 lies parallel to the global X3 and the local x2 axis lies on the global X1 X2 plane If the beam is a component of a sloped roof for example and must be aligned as shown in Figure b then the local x2 x3 axes must be rotated to coincide with the major
169. the stress distribution approaches linearity and the overall accuracy of the solution improves On the other hand increasing the number of elements in the model increases the solution time and increases the size of the files required to store the input data and results 1 7 1 Selection of the Computer Model The preparation of the model for two dimensional frames grids or trusses is usually very simple as each beam and column is represented by a single line element More complicated structures space frames or structures with area elements require more thought and good engineering judgment in the preparation of the model Typically structural members can be represented by either area elements or by line elements and the engineer must choose between them based on his experience Remember STRAP calculates numerically accurate results for the defined model It is the engineer s responsibility to define a model that correctly represents the structure thoroughly check for illogical or inconsistent results Version 12 5 1 7 1 12 06 STRAP Example 1 A square concrete plate of uniform thickness simply supported on all edges The plate should obviously be modeled by a regular pattern of quadrilateral elements How many elements are required for a sufficiently accurate solution The following table gives results for the center deflection of the plate 10x10 0 2 thick concrete Vertical deflection No of elements err
170. tion of a cylinder and a line The cylinder ts defined by 3 nodes on one of its circles Select additional nodes Modes will be created at the intersection of parallel lines through those nodes and the cylinder nens Define Each coordinate x1 42 X3 is defined by selecting a node Cat Cancel Intersection of plane amp line Select any three existing nodes that define the plane Select any two existing nodes that define the line The five nodes cannot lie on the same plane Version 12 5 2 5 12 06 STRAP I Select additional nodes Select a series of nodes the program creates nodes at the intersection of the plane and lines that are parallel to the original line but pass through the additional nodes For example Intersectian af cvlinder with plane Additional 4 nodes Additional nodes Parallel lines Intersection of cylinder amp line The new node is created at the intersection of a cylinder and a line e Select any three existing nodes that define the a circle on the cylinder the program assumes that the cylinder extends infinitely in both directions e Select any two existing nodes that define the line Note There are two intersection points the new node will be created at the point closest to the line end node a I Select additional nodes Select a series of nodes the program creates nodes at the intersection of the cylinder and lines that are parallel to the origina
171. tor matrix The eigenvalues correspond to the natural frequencies by the following equations eigenvalue w2 natural frequency w 2n Each value of the eigenvector is the relative displacement of the corresponding degree of freedom The mode shape of the lowest frequency longest period will be numbered 1 and all the others will be numbered respectively in ascending order The program assumes a lumped mass model i e the mass of the model is concentrated at the nodes The program solves the general eigenvalue problem using the Subspace Iteration method Explained simply the program bases the calculation of the eigenvalues in the current iteration on the eigenvalues of the previous iteration When the difference between the previous and current values is very small the program terminates the iteration process 6 2 Seismic Analysis This module calculates the earthquake response and the resulting moments and forces in the model based on the calculated mode shapes and Code related factors The mode shape analysis calculates n different mode shapes The maximum response deflection base shear etc for each shape is calculated from a Response Spectrum This spectrum is a graph which gives the acceleration as a function of the natural period T of the model The spectrum may be an idealized one taken from a Code e g Figure 1B in the SEAOC California Blue Book Code or it may be based on ground motion histories at the specific site
172. ts Equilateral triangles will produce the most accurate results Mesh Density The mesh density need not be constant throughout the model The program assumes a linear result distribution through the element If the actual result through the elements is not linear but parabolic for example it is obvious that there will be a decrease in the accuracy In a fine mesh the result diagram through any one element will always be approximately linear Increase the number of elements where there is a greater rate of change in the internal forces For example around supports where bending moments increase sharply openings and large concentrated loads To decrease the number of elements Use a rough mesh in areas where relatively low results are expected Remember that the connection to adjacent elements is through the element end nodes only and so nodes located along an edge of an element between end nodes are ineffective Use triangular or trapezoidal shaped elements to step between rough and fine quadrilateral meshes If you have doubts as to the accuracy of the results in a particular area of the model rerun the problem with a finer mesh in that area and compare results The results converge to the exact solution as the mesh becomes more refined Models with axes of symmetry Large symmetric structures can be modeled by defining only one half or a quarter of the model Note that the symmetry must be present in both the geometry and loading d
173. ures Part 1 1991 Eurocode 8 EC8 Design Provisions for Earthquake Resistance of Structures Part 1 2 1995 e ACI 318 05 Building Code Requirements for Reinforced Concrete refer to Appendix A8 3 e CSA A23 3 94 Design of Concrete Structures 8 456 2000 Code of Practice for Plain and Reinforced Concrete IS 13920 1993 Ductile Detailing of Reinforced Concrete Structures Subjected to Seismic Forces NBr 6118 2000 Brazil Note that the manual uses the following terminology MEMBER refers to a STRAP beam element BEAM refers to a continuous beam consisting of a series of connected MEMBERS defined in this postprocessor Beams are defined by the user COLUMN refers to a column consisting of a series of connected MEMBERS defined in this postprocessor Columns must be defined by the user SPAN refers to a span between supports in a BEAM or COLUMN that may be comprised of more than one MEMBER WALL refers only to a wall defined using the STHAP Wall option Walls are identified automatically by the program Quad and triangular elements cannot be designed as walls SLAB refers to a plane of quad and or triangular elements Slabs are identified automatically by the program The terms STIRRUPS American and LINKS British are identical 8 1 1 Creating a concrete structure from a STRAP model The Concrete Postprocessor must design beams columns and walls separately because the design methods
174. urrent stage Select beams using the standard element selection options Inactive elements are not displayed Restore an element to the current stage Models may contain both beam elements and finite elements e the end nodes of plane strain finite elements do not transfer bending moments to adjacent elements i e the corners of these elements are all released Referring to the shear wall in Figure a if the lintel beams are modeled by beam elements as shown in Figure b no ra moments will be generated in them The beams should be extended into the wall as shown in Figure c Version 12 5 2 14 12 06 STRAP 2 5 Springs Define linearly elastic spring supports translational and rotational at nodes When an elastic support is defined in a specific direction at a node the node must be unrestrained in that To define or revise springs define To delete springs Q D O D To write the spring constant values on the graphic display for defined springs x 2 E m Define translational springs that act in the positive or negative direction only of the selected axis but not both EL FH Define spring constant per area length and then select elements nodes defining area length program lear will automatically calculate spring constants for relevant nodes To revise a spring select Define select the node and enter the revised value Note To define a translational spring in a direction not parall
175. ways in the same direction as the result coordinate system X axis Y can be at any angle a from X Normally a 90 and the program assumes this value if no other value is defined The design moments Mx and My for reinforcement design are calculated according to the Wood and Armer equations in the direction of X Y The following figure shows an example with a gt 90 AZ Al The axes parallel to the main directions of reinforcement are denoted by X and Y The program always assumes X to be parallel to the result X axis In most reinforced concrete slabs the two reinforcement directions are perpendicular This is the default assumption of the program For all other cases the skew angle a between X and Y must be defined The program will then calculate the design moments for reinforcement in the directions of the reinforcement coordinate axes X and Y Version 12 5 5 5 12 06 STRAP 5 3 Graphic Results 5 3 1 Results at Element Centres To display the model geometry with the numerical value of the result written at the centre of each element For example This option superimposes the tabular results at the element centre on the geometry display The values are the same as those displayed in the tables Note e Results are displayed according to the Default element result coordinate System unless the result system was revised for specific elements Options Element results coord s
176. will prompt for a file name Note that these drawings cannot be edited using the Print edit saved drawing option Save for Print edit drawing option To save the drawing so that it can be edited and printed using the Print edit saved drawing option These drawings can only be printed by STRAP and not by other programs or utilities Click the button to start printing Version 12 5 1 9 7 12 06 STRAP 1 9 9 2 Rendered drawing Use this option to print the current rendered display directly to the printer or to a file The printed display will be enclosed in a frame and will include a header Send output to alg CELHA Setup Width Height Size mm Size mm i Full Full C Fit size to content i Fit size to content Send output to file Cancel Width Height Select the height and width of the printed drawing Note that Windows will distort the image if you do not maintain the original proportions Select one of the following options for width and or height Size Specify the actual dimension in millimeters f Full The drawing will fit exactly into the page width height Fit size The program will automatically calculate the dimension required to maintain the original drawing proportion Note to maintain the original proportions adjust either the width or the height while specifying Fit size to content for the other dimension All other options Refer to 1 9 9 1 1
177. with it Element properties certain loads member end and internal forces are referred to this local coordinate system The local axes directions are automatically specified by the program according to default conventions when the elements are defined but may be revised by the user Beam elements refer to 1 8 2 1 e Quadrilateral finite elements refer to 1 8 2 2 e Triangular finite elements refer to 1 8 2 3 e Wall elements referto 1 8 2 4 1 8 2 1 Beam Elements The directions of the local axes determine e the orientation of the sections major and minor axes which are always aligned with the x2 x3 axes e the direction of beam loads which are always parallel to the x2 x3 axes Default Convention Plane models Axis Direction x1 Always coincides with the centroidal axis of the beam the positive direction is from the start node JA in the geometry tables to the end node JB as specified during the definition of the beam x2 Aea anans are tron 2 saben wit remp cun As x1 and x3 are known x2 is determined from the right hand rule x3 Always parallel to the global X3 axis parallel to the global X3 axis Version 12 5 1 8 2 12 06 STRAP Examples x1 xI JB OT x1 dv de Global coordinate system xalocal x3 v Space models Direction duis General case x1 not parallel to X3 Special case x1 parallel to X3 x1 Always coincides with the centroidal axis of the As in general case beam
178. you want to define modify the tutorial models Refer to 1 3 3 To print the Tutorial User s Manual refer to Appendix A2 Version 12 5 1 1 2 12 06 STRAP 1 2 Running the program The program Main Menu is displayed when the STRAP icon is selected in the Windows screen or when the B Models tab is clicked in any of the program modules e the program lists the existing models in the current directory sorted alphabetically by date or by model number e clicking on any line highlights the model title the program displays the latest view of the model and its statistics at the bottom of the screen clicking on a tab below the toolbar will initiate the relevant option for the highlighted model e multiple models may be selected for the delete and copy model options ER STRAP models list C STRAP 27 10 02 27 10 02 06 11 02 06 11 02 196 06 11 02 06 11 02 195 Dynamic analysis north tower 22 10 02 22 10 02 153 floor at 4 70 2340 02 2310 02 173 floor at 7 70 16 10 02 16 10 02 162 t frame b 15 06 03 15 06 03 152 02 06 02 02 06 02 061 mit u truss Fa The list of model titles is displayed sorted according to any of the four columns in the table e model title date revised e date solved e model number To sort the models according to one of the columns click on the column header a will be displayed alongside the column header indicating that the column is sor
179. ystem in Menu bar e the program does not change the sign of the results even if the directions of the local axes are inconsistent local stress or moment concentrations at element corners e g from a joint load applied at a node or a support reaction are not displayed Display Contour map or Results Along a Line for a more complete picture 5 3 2 Result Contour Map To display the model geometry with a contour map of the results superimposed Each line of the contour map gives the location of a specified value of the result For example This option creates a contour plot from the element centre and corner results In order to produce smooth and continuous contours the program averages the exact corner results from all the elements connected to a particular node as well as along the edges of two adjacent elements Referring to the explanation for Results along a Line it is obvious that this averaging of results may lead to a discrepancy between the corner results from the tables and the contour map Results are displayed according to the Default element result coordinate system unless the result system was revised for specific elements Options Element results coord system in Menu bar Space models WARNING The local x3 axis direction is not reversed as in plane models If the x3 axes of adjacent elements are in opposite directions the sign of the results will be inconsistent and their interpolation over the

Windows

Contents

Download Pdf Manuals

Related Search

Related Contents