2013 STUDENT STEEL BRIDGE COMPETITION STRUCTURAL ANALYSIS, DESIGN, AND DRAWING PRODUCTION USING BENTLEY PRODUCTS

Transcription

1 2013 STUDENT STEEL BRIDGE COMPETITION STRUCTURAL ANALYSIS, DESIGN, AND DRAWING PRODUCTION USING BENTLEY PRODUCTS

2 AISC/ASCE STUDENT STEEL BRIDGE COMPETITION 2013 ANALYSIS, DESIGN AND DOCUMENTATION OF STEEL BRIDGES USING STAAD.Pro V8i AND STRUCTURAL MODELER INTEGRATION By RAVINDRA OZARKER, P.E., P.ENG. September 15,

3 Table of Contents 1.0 Introduction Creating the Bridge Geometry/Structural Analysis Step-by-Step Tutorial Exercise 1: Overall Bridge Geometry 21 Exercise 2: Creating the Leg Structure. 30 Exercise 3: Modifying the Deck Geometry.. 40 Exercise 4: Creating Member Offsets 51 Exercise 5: Physical Member Formation.. 61 Exercise 6: Truss Specification Creation and Assignment Exercise 7: Support Creation and Assignment. 66 Exercise 8: Property Creation and Assignment 67 Exercise 9: Formation of Cantilever Section 74 Exercise 10: Creating Load Cases & Items.. 83 Exercise 11: Performing Analysis 91 Exercise 12: Understanding the Results 92 Exercise 13: Design of the Structure using AISC STAAD.Pro and Structural Modeler Integration Help, Questions, Comments 118 3

4 Appendices A: Creating Bridge Geometry Using STAAD.Pro V8i Grid System B: Creating Bridge Geometry Using STAAD.Pro V8i dxf Import C: STAAD.Pro Input Command File D: Specifying Proper Slenderness Lengths in STAAD.Pro E: Dataset Installation

5 1.0 Introduction The Student Steel Bridge Competition is sponsored by the American Institute of Steel Construction (AISC), American Society of Civil Engineers (ASCE) and cosponsored by the American Iron and Steel Institute (AISI), Bentley Systems, Inc., Canadian Institute of Steel Construction (CISC), James F. Lincoln Arc Welding Foundation, National Steel Bridge Alliance (NSBA), Nelson Stud Welding, Nucor Corporation, and Steel Structures Education Foundation (SSEF). Students design and erect a steel bridge by themselves but may seek advice from faculty and student organization advisers. Civil Engineering students are challenged to an inter-collegiate competition that includes design, fabrication, and construction of a scaled steel bridge. Participating students gain practical experience in structural design, fabrication processes, construction planning, organization, project management, and teamwork. In the industry, commercial structural analysis and design software integrated within a BIM (Building Information Modeling) or BrIM (Bridge Information Modeling) environment are used extensively to complete projects on time and at the same time lets engineers maintain accuracy and come up with very efficient design alternatives. The correct combination of software tools can make the bridge design, fabrication and construction task very easy. STAAD.Pro is the professional s choice for steel, concrete, timber, aluminum and cold-formed steel structures, culverts, petrochemical plants, tunnels, bridges, piles and much more. It is a general purpose structural analysis and design tool. Structural Modeler is an advanced, yet intuitive and easy-to-use building information modeling (BIM) application that empowers structural engineers and designers to create structural system models and related engineering drawings (i.e. documentation). 5

6 STAAD.Pro and Structural Modeler are integrated. STAAD.Pro models can be imported into Structural Modeler and Structural Modeler models can be exported out to STAAD.Pro. The purpose of this document is to help students analyze and design their bridge models using Bentley s STAAD.Pro software and produce engineering layout drawings using Structural Modeler. This document does not teach how to compare advantages of various alternatives that are allowed in this competition. Designers must consider carefully the comparative advantages of various alternatives. For example, a truss bridge may be stiffer than a girder bridge but slower to construct. Successful teams analyze and compare alternative designs prior to fabrication. Following are some statements from the Student Steel Bridge Competition 2013 Rules manual. This Year s Problem Statement: The new Hill Music Hall and Marian Paroo Memorial Library sparked revitalization of the River City waterfront, with restaurants, theaters, and luxury condominiums scrambling for space in the old brick warehouses. The resulting vehicle traffic now exceeds the capacity of city streets. Therefore, the River City Development Corporation (RCDC) is requesting design/build proposals for a bridge to provide direct access from suburbs across the river. Construction Speed The bridge with the lowest total time will win in this category. Construction Economy The bridge with the lowest construction cost (Cc) will win in the construction economy category. Construction cost is computed as Cc = Total time (minutes) x number of builders x 50,000 ($/builder-minute) + load test penalties ($). Total time is defined in 7.2.3, and load test time penalties are prescribed in 12.2, 12.4, and The number of builders includes all members and associates of the competing organization who physically assist the team at any time during timed construction or repair. Lightness The bridge with the least total weight will win in the lightness category. Total weight is the weight of the bridge (determined by scales provided by the host student organization) plus weight penalties prescribed in 9.3, 9.4, and Decking, tools, temporary pier, lateral restraint devices, and posters are not included in total weight. Stiffness The bridge with the lowest aggregate deflection will win in the stiffness category. Aggregate deflection is determined from measurements as prescribed in Structural Efficiency The bridge with the lowest structural cost (Cs) will win in the structural efficiency 6

7 category. Structural cost is computed as For a bridge that weighs 400 pounds or less, Cs = Total weight (pounds) x 10,000 ($/pound) + Aggregate deflection (inches) x 1,000,000 ($/inch) + Load test penalties ($) For a bridge that weighs more than 400 pounds, Cs = [Total weight (pounds)]2 x 25 ($/pound2) + Aggregate deflection (inches) x 1,000,000 ($/inch) + Load test penalties ($) Total weight is defined in 7.2.4, aggregate deflection is defined in 7.2.5, and load test weight penalties are prescribed in 12.4 and Overall Performance The overall performance rating of a bridge is the sum of construction cost and structural cost, (Cc + Cs). The bridge achieving the lowest value of this total wins the overall competition. 7

8 Overall Performance The overall performance rating of a bridge is the sum of construction cost and structural cost (Cc + Cs). The bridge achieving the lowest value of this total wins the overall competition. From the above statements it is clear that a bridge that is light and stiff (i.e. structurally efficient) may not necessarily be an overall winner. Designers need to keep other criteria such as constructability and cost (i.e. construction economy) in mind. This document and software packages discussed here will help students analyze and understand their structures better to achieve structural efficiency. The documentation that will be produced can be used to discuss/plan construction economy. 8

9 2.0 Creating the Bridge Geometry/Structural Analysis STAAD.Pro can make your bridge design and analysis task easier. The bridge geometry in STAAD.Pro can be constructed in many ways: 1. STAAD.Pro user interface 2. Structure Wizard 3. Using a DXF import (importing a dxf MicroStation or AutoCAD drawing) 4. Structural Modeler 5. ProSteel 3D In this case part of the bridge geometry will be created using Structure Wizard. The bridge geometry is shown in Figure 1. 9

10 Note: The bridge model constructed in this tutorial does not fully comply with the 2013 rules. For example, the maximum allowable length of the bridge is 17 feet. This tutorial illustrates a model bridge with 21 feet span. There are other grometric contrains that the designers need to be aware of. The goal of this tutorial is to show designers how these complex bridge models can be analyzed and designed using STAAD.Pro. (a) Bridge Geometry Discussed In This Tutorial (b) Property Assignment 10

11 (c) Lateral Load Test 11

12 (d) Vertical Load Test Step 1 (e) Vertical Load Test Step 2 Figure 1: Bridge Geometry and Loading Process 12

13 Note: If custom cross sections are used for the bridge members, the custom shapes can be modeled as General Sections. You may have to use STAAD.SectionWizard. Alternatively, a General Section can be also created in STAAD.Pro V8i using the instructions on the following link: ftp://ftp2.bentley.com/dist/collateral/web/building/staadpro/modeling_custom Shapes in STAAD_PRO.pdf The loads on the bridge will be placed based upon the roll of first dice. The following table shows the possible values of L and locations where the displacements will be measured. Note: The loading on the bridge model constructed in this tutorial does not fully comply with the 2013 rules. The goal of this tutorial is to show designers how these complex bridge models can be analyzed and designed using STAAD.Pro. In this tutorial, the following load pattern will be used. 13

14 Following are all possible values of L and LC based on the roll of the two dice. DICE 1 DICE 2 L (FT) TB (FT) TC (FT)

15 Loading Type L=0 ft VLT PRELOAD L=0 ft VLT STEP 1 L=0 ft VLT STEP 2 Table 1: Bridge Loading Components Self weight of the structure Distributed Load as shown below: VLT PRELOAD Left Side: 0.2 kip/(4 beams * 3ft deck) = k/ft load on each member. Right Side: 0.05 kip/(4 beams * 3ft deck) = k/ft load on each member. VLT STEP 1: Left Side: 1.8 kip/(4 beams * 3ft deck) = 0.15 k/ft load on each member. Right Side: 0.05 kip/(4 beams * 3ft deck) = k/ft load on each member. VLT STEP 2: Left Side: 1.8 kip/(4 beams * 3ft deck) = 0.15 k/ft load on each member. Right Side: 0.7 kip/(4 beams * 3ft deck) = k/ft load on each member. L=3 ft VLT PRELOAD L=3 ft VLT STEP 1 L=3 ft VLT STEP 2 Self weight of the structure Distributed Load as shown below: VLT PRELOAD Left Side: 0.2 kip/(4 beams * 3ft deck) = k/ft load on each member. Right Side: 0.05 kip/(4 beams * 3ft deck) = k/ft load on each member. VLT STEP 1: Left Side: 1.8 kip/(4 beams * 3ft deck) = 0.15 k/ft load on each member. 15

16 Right Side: 0.05 kip/(4 beams * 3ft deck) = k/ft load on each member. VLT STEP 2: Left Side: 1.8 kip/(4 beams * 3ft deck) = 0.15 k/ft load on each member. Right Side: 0.7 kip/(4 beams * 3ft deck) = k/ft load on each member. L=6 ft VLT PRELOAD L=6 ft VLT STEP 1 L=6 ft VLT STEP 2 Self weight of the structure Distributed Load as shown below: VLT PRELOAD Left Side: 0.2 kip/(4 beams * 3ft deck) = k/ft load on each member. Right Side: 0.05 kip/(4 beams * 3ft deck) = k/ft load on each member. VLT STEP 1: Left Side: 1.8 kip/(4 beams * 3ft deck) = 0.15 k/ft load on each member. Right Side: 0.05 kip/(4 beams * 3ft deck) = k/ft load on each member. VLT STEP 2: Left Side: 1.8 kip/(4 beams * 3ft deck) = 0.15 k/ft load on each member. Right Side: 0.7 kip/(4 beams * 3ft deck) = k/ft load on each member. 16

17 L=7 ft VLT PRELOAD L=7 ft VLT STEP 1 L=7 ft VLT STEP 2 Self weight of the structure Distributed Load as shown below: VLT PRELOAD Left Side: 0.2 kip/(4 beams * 3ft deck) = k/ft load on each member. Right Side: 0.05 kip/(4 beams * 3ft deck) = k/ft load on each member. VLT STEP 1: Left Side: 1.8 kip/(4 beams * 3ft deck) = 0.15 k/ft load on each member. Right Side: 0.05 kip/(4 beams * 3ft deck) = k/ft load on each member. VLT STEP 2: Left Side: 1.8 kip/(4 beams * 3ft deck) = 0.15 k/ft load on each member. Right Side: 0.7 kip/(4 beams * 3ft deck) = k/ft load on each member. 17

18 L=9 ft VLT PRELOAD L=9 ft VLT STEP 1 L=9 ft VLT STEP 2 Self weight of the structure Distributed Load as shown below: VLT PRELOAD Left Side: 0.2 kip/(4 beams * 3ft deck) = k/ft load on each member. Right Side: 0.05 kip/(4 beams * 3ft deck) = k/ft load on each member. VLT STEP 1: Left Side: 1.8 kip/(4 beams * 3ft deck) = 0.15 k/ft load on each member. Right Side: 0.05 kip/(4 beams * 3ft deck) = k/ft load on each member. VLT STEP 2: Left Side: 1.8 kip/(4 beams * 3ft deck) = 0.15 k/ft load on each member. Right Side: 0.7 kip/(4 beams * 3ft deck) = k/ft load on each member. 18

19 L=12 ft VLT PRELOAD L=12 ft VLT STEP 1 L=12 ft VLT STEP 2 Self weight of the structure Distributed Load as shown below: VLT PRELOAD Left Side: 0.2 kip/(4 beams * 3ft deck) = k/ft load on each member. Right Side: 0.05 kip/(4 beams * 3ft deck) = k/ft load on each member. VLT STEP 1: Left Side: 1.8 kip/(4 beams * 3ft deck) = 0.15 k/ft load on each member. Right Side: 0.05 kip/(4 beams * 3ft deck) = k/ft load on each member. VLT STEP 2: Left Side: 1.8 kip/(4 beams * 3ft deck) = 0.15 k/ft load on each member. Right Side: 0.7 kip/(4 beams * 3ft deck) = k/ft load on each member 19

20 Weight of the structure Lateral Load Self weight of the structure Self weight of the structure Distributed Load as shown below: kip/(2 beams * 3ft deck) = k/ft load on each member kip point Load as shown below Notes: (1) L is defined in Section 8 of the document entitled Student Steel Bridge Competition Rules 20

21 3.0 Step-by-Step Tutorial Exercise 1: Overall Bridge Geometry 1. Launch STAAD.Pro by clicking on the Start->All Programs->STAAD.Pro V8i->STAAD.Pro icon. The STAAD.Pro V8i introduction screen will appear as shown in Figure 2. Note: Make sure that US Design Codes is checked and has a green light besides it. The US Design Codes is not checked, you will need to check this box and close the STAAD.Pro interface and re-open it again. Figure 2: STAAD.Pro Introduction Screen 2. Click on File->Configure. The Configure Program dialog box will appear. Make sure that the Base Unit is set to English. Note: If you will be constructing your bridge model in the metric unit system, make sure that you set the base unit system to Metric. 21

22 Figure 3: Base Unit System Setup 3. Click on the File->New menu command. The New dialog box will appear. 4. Provide the model options as shown in Figure 4. Figure 4: The New Dialog box 5. Click on the Next button. The Where do you want to go Today? Dialog box will appear as shown in Figure Click on the Finish button. 7. The STAAD.Pro V8i user interface will appear as shown in Figure 6. 22

23 Figure 5: The Where do you want to go Today? dialog box Figure 6: STAAD.Pro User Interface 8. You could create the bridge geometry using the grid options shown in Figure 6. Appendix A of this document illustrates the procedure of creating a simple bridge geometry using the grid system. You could also create a bridge geometry using MicroStation XM and export that drawing as a dxf. Appendix B discusses how this can be achieved. In this tutorial, the Structure Wizard will be used to create the bridge geometry. 9. Click on the Geometry->Run Structure Wizard menu command. The Structure Wizard user interface will appear as shown in Figure 7. 23

24 Figure 7: Structure Wizard User Interface 10. Double click on the Pratt Truss icon on the left. The Select Parameters dialog box will appear as shown in Figure 8. Note: In this dialog box, you can adjust the bay-to-bay spacing by simply clicking on the icon. Make sure that the summation of the bay-spacing is equal to total length and width that you have specified respectively. Figure 8: Structure Wizard User Interface 11. Input the parameters in the Select Parameters dialog box as illustrated in Figure Press the Apply button. The structural geometry will appear as shown in Figure 9. 24

25 Figure 9: Bridge Structure Geometry in Structure Wizard 13. To transfer the structure to STAAD.Pro, select the File->Merge Model With STAAD.Pro Model menu command. Structure Wizard interface will close and a conformation dialog box will appear. Figure 10: Confirmation dialog box 14. Click Yes for the conformation dialog box. The Paste Prototype Model dialog box will appear. 15. Click on the Ok button. The bridge geometry will be created in STAAD.Pro as shown in Figure

26 Note: The Y Axis should be the axis of gravity in your STAAD.Pro models. Figure 11: Bridge geometry in STAAD.Pro interface 16. The bridge geometry seen in Figure 11 has to be mirrored in the XZ-plane. 17. Select the Beams Cursor from the left hand side. Figure 12: Beams Cursor 18. Select all the beams in the graphics window. Ctrl + A will select all the beams in the model. 19. Click on Geometry->Mirror command. The Mirror dialog box will appear as shown in Figure

27 Figure 13: The Mirror dialog box 20. Input the mirror parameters as shown in Figure Click the OK button. The structure will be mirrored about the X-Z plane as shown in Figure 14. Figure 14: Bridge structure is mirrored about the X-Z plane 27

28 Note: Basic 3D Navigation Tools: Use the arrow keys on the keyboard to rotate structure, the middle mouse roller button to zoom in and out. If you press the roller button and hold it down, you will be able to pan. You may also use the icons in the icon bar. (i.e. ) 22. Select the node points as shown in Figure 15 using the nodes cursor. Figure 15: Node points selected 23. Select the Geometry->Translational Repeat menu command. Figure 16: Translational repeat command selected 24. Select the Geometry->Translational Repeat menu command. 28

29 Figure 17: Translational repeat command selected 25. The 3D Repeat dialog box will appear as shown in Figure 17. Input the mirror parameters as shown in Figure Click the Ok button. The legs of the bridge structure will appear as shown in Figure 18. Figure 18: Legs of the bridge are created 29

30 Exercise 2: Creating the Leg Structure 1. Select the leg members and right click with the mouse and select the Insert Node option. Figure 1: Legs of the bridge are created 2. Select the leg members and right click with the mouse and select the Insert Node option. Figure 2: Legs of the bridge are created 3. Click the Ok button. The legs of the bridge structure will be subdivided to create the lattice leg attachment points. 30

31 Figure 3: Legs of the bridge are created 4. Select the node point on the bottom left hand side corner. Figure 4: Legs of the bridge are created 5. Select the node point on the bottom left hand side corner. 6. Right click on the screen and select the copy command. This will copy the highlighted node to the memory. 31

32 Figure 5: Legs of the bridge are created 7. Right click on the screen and select the Paste command. The Paste with Move dialog box will appear. Figure 6: Legs of the bridge are created 32

33 Figure 7: Legs of the bridge are created 8. Input the parameters as illustrated in Figure 7 and Press the Ok button. You will note a new node point at the lower left hand side of the structure. Figure 8: Legs of the bridge are created 9. Select the Geometry->Add Beam->Add beam from Point to Point menu command. 33

34 Figure 9: Legs of the bridge are created 10. Connect the nodes with a new beam element as shown in Figure Delete all the leg members except the member that was created in the above step and the small lattice leg attachment points. Figure 10: Legs of the bridge are created 12. Divide the beam into three equally parts. Right click on the beam and select the Insert Node command. 13. Input the information in the Insert Nodes dialog box as shown in Figure is entered in the n= input box. 34

35 Figure 11: Insert nodes dialog box 14. Click the Ok button. 15. Select the new leg members as shown in Figure 12. Figure 12: The beam members are selected 16. Select the Geometry->Circular Repeat menu command. 17. The 3D Circular dialog box will appear. Input the data in the 3D Circular dialog box as shown in Figure

36 Figure 13: 3D Circular dialog box 18. Click on the node icon as shown in Figure 13. Select the node point as shown in Figure 14. Figure 14: Node point is clicked 19. Press the Ok button. The leg members will be created as shown in Figure 15. Figure 15: Lattice leg member is created 36

37 20. Select the lattice leg member as shown in Figure Right click on select the Copy command. Figure 16: Copy command is selected 22. Right click on select the Paste Beams command. The Paste with Move dialog box will appear. Figure 17: Paste Beams command is selected 23. Press the Reference Pt. button. The Specify Reference Point dialog box will appear. Figure 18: Reference Pt. button is pressed 37

38 Figure 19: Specify Reference Point dialog box 24. Press the Ok button and click on the lower node of the lattice leg attachment points to create the rest of the leg members as shown in Figure 20. Figure 20: Rest of the leg members are created 38

39 25. Press the Ok button and click on the lower node of the lattice leg attachment points to create the rest of the leg members as shown in Figure

40 Exercise 3: Modifying the Deck Geometry 1. Select the members as shown in Figure 1. Press the delete key on your keyboard to delete these members. Figure 1: Members are being deleted 2. Draw a member as shown in Figure 2. Figure 2: New Member is created 3. Select all members in the model by pressing the CTRL+A key on the keyboard. 40

41 Figure 3: Intersect menu command 4. Select the Geometry->Intersect Selected Members->Intersect command menu. 5. Press the Ok button. 6. Select the members as illustrated in Figure Press the delete key on the keyboard. 8. Select the member as illustrated in Figure 5. Figure 4: Intersect menu command 41

42 Creating Additional Members: Figure 5: Member 14 selected 9. Right click and select the insert node command. 10. Click on the Add Mid Point button and click on the ok button in the Insert Nodes dialog box. 11. Select the member as illustrated in Figure 6. Figure 6: Member 14 selected 12. Segment the beam at the following locations as shown in Figure 7. 42

43 Figure 7: Member 14 is being segmented 13. Click the Ok button. Figure 8: Member 154 is selected 14. Select a beam as shown in Figure Segment the beam at the following locations as shown in Figure Click the Ok button. 43

44 17. Select a beam as shown in Figure 10. Figure 9: Member 154 is being segmented Figure 10: Member 153 is selected 18. Segment the beam at the following locations as shown in Figure Click the Ok button. 44

45 Figure 11: Member 153 is being segmented 20. Add new beam members as shown in Figure 12. Figure 12: New members are added 21. The next bay members will be subdivided similarly. Select the member as shown in Figure

46 Figure 13: Member is selected 22. Right click and select the Insert Node command. Input the data in the Insert Nodes dialog box as illustrated in Figure Click the Ok button. Figure 14: Member is being divided into smaller pieces 46

47 Figure 15: Member is selected 24. Select the member as shown in Figure 15. Figure 16: Member is being divided into smaller pieces 25. Right click and select the Insert Node command. Input the data in the Insert Nodes dialog box as illustrated in Figure

48 Figure 17: Members are selected They will be mirrored about the Y-Z plane. 26. Click the Ok button. 27. Add new beam members as shown in Figure Select the beams shown in Figure 17. Select the Geometry->Mirror menu command. The Mirror dialog box will appear. Figure 18: Mirror dialog box 48

49 29. Input the information in the Mirror dialog box as shown in Figure 18. Note that node 11 at X=10.5 maybe different in the model that you have constructed. Please use the node icon to pick a suitable point on the mirror plane. Figure 19: Members are mirrored Figure 20: Member is selected 30. Select the member as shown in Figure Right click and select the Insert Node command. 32. The Insert Nodes dialog box will appear. Input the parameters as shown in Figure Press the Ok button. 49

50 Figure 21: Member is being divided into smaller pieces Figure 22: Final Geometry 50

51 Exercise 4: Creating Member Offsets 1. Select the General->Spec control tab on the left. 2. Press the Beam button in the data area. 3. Select the Offset tab in the Member Specification dialog box. 4. Enter the inputs as shown in Figure Press the Add button. You will note that the START specification command will appear on the right hand side. Figure 1: Member Start end offset 6. Press the Beam button in the data area. 7. Select the Offset tab in the Member Specification dialog box. 8. Enter the inputs as shown in Figure Press the Add button. You will note that the END specification command will appear on the right hand side. 51

52 Figure 2: Member end node offset 10. Select the member as shown in Figure Select the START specification command. Press the Assign button. 12. Select the End specification command. Press the Assign button. Figure 3: Select the segmented member 13. Select the End specification command. Press the Assign button. 52

53 14. Draw a beam from Node 1 to Node 2 as illustrated in Figure 4. Figure 4: Select the segmented member 15. This beam is created because we need to model two beams that are running parallel to each other and sandwiching intermediate members as illustrated in Figure 5. Figure 5: 3D illustration of member offset 16. Check the Highlight Assigned Geometry check box. 17. Select the End specification command. 18. Click the Select->By Inverse-> Inverse Geometry Selection menu command. 53

54 Figure 6: Inverse Geometry Selection command 19. Click the View>View Selected Objects Only menu command. Select the Geometry cursor. Press the Ctrl+A. 20. Click the Geometry->Break Beam at selected node point menu command. 54

55 Figure 7: Inverse the geometry selection Figure 8: Break Beams at Selected Nodes menu command selected 55

56 21. Select the General->Spec control tab on the left. 22. Press the Beam button in the data area. 23. Select the Offset tab in the Member Specification dialog box. 24. Enter the inputs as shown in Figure Press the Add button. You will note that the START specification command will appear on the right hand side. 26. Press the Beam button in the data area. Figure 9: Member Start end offset 27. Select the Offset tab in the Member Specification dialog box. 28. Enter the inputs as shown in Figure Press the Add button. You will note that the END specification command will appear on the right hand side. 56

57 Figure 10: Member End node offset 30. Select the member as shown in Figure Select the START specification command. Press the Assign button. 32. Select the End specification command. Press the Assign button. Figure 11: Select the members 57

58 33. Click on View->Whole Structure menu command. 34. Select the View from +Z icon. 35. Select the members as shown in Figure 12 by rubberbanding the top cord members. Figure 12: Select the members 36. Select the Isometric View icon 37. Press and hold the Ctrl key on the keyboard and click on the members that need to be removed from the current selection as shown in Figure 13. Figure 13: Unselect the members 38. Select the Geometry->Translational Repeat command. The 3D Repeat box will appear. 58

59 Figure 14: Translational Repeat Command 39. Select the Geometry->Translational Repeat command. Enter the parameters as shown in the 3D Repeat dialog box in Figure 15. Figure 15: 3D Repeat Dialog box 40. Press the Ok button. The selected geometry will be copied to the other side of the bridge. 59

60 Figure 16: Members are missing 41. Node that in some instances STAAD may not copy two members between the same node points as illustrated in Figure 16. The user has to manually create these members using the draw beam from point-to-point menu command and apply the correct offsets. 42. The final bridge geometry is illustrated in Figure 17. Figure 17: Final Bridge Geometry 60

61 Exercise 5: Physical Member Formation 1. Select the Select->Beams Parallel To->X axis menu command. Figure 1: Select Beams Parallel to X Axis menu command 2. Select the Select->Beams Parallel To->X axis menu command. 3. Select the View->View Selected Objects Only menu command. 4. Select the View from +Z icon. 5. Select the members as shown in Figure 2 by rubberbanding the top cord members. Figure 2: Top chord members of bridge are selected 6. Select the View->New View menu command. 7. Click the Ok button. 8. Select the View from +Z icon. 61

62 9. Select the members as shown in Figure 3 (i.e. plan view of top chord members) by rubberbanding the top cord members. (Just one side). Figure 3: Select the members 10. Right click and select the Form Member option. 11. Select the members as shown in Figure 4 by rubberbanding the top cord members. 12. Right click and select the Form Member option. Figure 4: Select the members 13. Repeat the above two steps for the remaining two member rows. 14. Select the Physical member cursor. 15. Click on a member. You will note that the entire Physical Member can be selected with a single click. 16. Click on the View->Whole Structure menu command. 62

63 Exercise 6: Truss Specification Creation and Assignment 1. Click on the General->Spec menu command. 2. Click on the Beam button. The Member Specification dialog box will appear as shown in Figure 1. Figure 1: Select the members 3. Select the Truss tab in the Member Specification dialog box. 4. Press the Add button. 5. Select the Member Truss specification from the right hand side data area. 6. Select the View from +z icon ( ). 7. Select the members as shown in Figure 2. 63

64 8. Press the Assign button on the right hand side. Figure 2: Select the members 9. The Truss specification will appear in the graphics window. Figure 3: Select the members Note: Assigning too many releases may make the structure unstable. Pay close attention to how the beam elements will behave in the real structure and the type of connections that are provided at the joints. Always check the Statics Check in the post processing mode to make sure that the structure is in equilibrium for all load cases. 64

65 Exercise: Create the highlighted members using the tools that you have learned: 65

66 Exercise 7: Support Creation and Assignment 1. Select the General->Property control tab on the left. 2. Click on the Create button on the right hand side Data Area. The Create Support dialog box will appear. Figure 1: Create Support dialog box 3. Click on the Pinned tab. 4. Click on the Add tab. 5. Select the S2 Support 2 entry in the data area. 6. View the structure from +Z using the ( ) icon. 7. Select the nodes cursor( ). 8. Rubberband the nodes at the base and assign the pinned supports. 66

67 Exercise 8: Property Creation and Assignment Figure 1: Member Properties 1. Open the My Bridge_1.std file if you have not followed the previous exercises. 2. Click the General tab on the left. 3. Click on the Section Database button in the data area. 4. Select the Tube property item in the Section Profile Tables dialog box and provide the inputs as shown in Figure 2. Note: The unit converter can be launched by pressing the F2 key. If you enter 2 and press the enter key in the unit converter, the text box will display the dimension converted to the default unit system being used in your model. The space is required between the dimension and the unit for the unit converter. For example, 12in will not work but 12 in will work. 67

68 5. Click the Add button. Figure 2: Property Definition 6. Provide the inputs as shown in Figure 3 in the Section Profile Tables dialog box. 7. Click the Add button. Figure 3: Property Definition 8. Provide the inputs as shown in Figure 4 in the Section Profile Tables dialog box. 68

69 Figure 4: Property Definition 9. Click the Add button. Figure 5: Property Definition 10. Select the inputs as shown in Figure Click the Add button. 12. Click the Close button. The property definitions should appear in the Properties dialog box in the Data Area. 69

70 Figure 6: Properties dialog box 13. Select the first tube property in the Properties dialog box in the Data Area. 14. Select the members as shown in Figure 7. Figure 7: Member Selection 70

71 15. Select the Assign to Selected Beams assignment option in the Properties dialog box. 16. Click on the Assign button. The property reference number will appear in the graphics window. 17. Select the second tube property in the Properties dialog box in the Data Area. 18. Select the members as shown in Figure 8. Figure 8: Member Selection 19. Click on the Assign button. The property reference number will appear in the graphics window. 20. Select the third tube property in the Properties dialog box in the Data Area. 21. Select the members as shown in Figure 9. Figure 9: Member Selection 71

72 22. Click on the Assign button. The property reference number will appear in the graphics window. 23. Select the PIPS20 property in the Properties dialog box in the Data Area. 24. Select the members as shown in Figure 10. Figure 10: Member Selection 25. Click on the Assign button. The property reference number will appear in the graphics window. 26. Click anywhere in the white space in the graphics window to get rid of the member selection. Right click in the Graphics Window and select the 3D Rendering. The rendered view of the structure will appear in a separate window as shown in Figure

73 Figure 11: 3D Rendered View of the structure Note: Standard AISC sections are available by clicking the Section Database button on the right. In the American Databases, Pipes and Tubes can be created using the Tubes and Pipes items in the Section Profile dialog box. The American section database can be modified by clicking on Tools->Modify Section Database menu command. 73

74 Exercise 9: Formation of Cantilever Section 1. Open the My Bridge_2 file if you have not followed Exercises 1 to Click on the view from positive z icon ( ) to see an elevation view of the structure. 3. Click on the Geometry control tab on the left hand side of the screen. 4. Click on the Nodes cursor ( ) 5. Select the node as shown in Figure 1. The information for the node point will be displayed on the right hand side Nodes Table. Figure 1: Nodes table is displayed on the right Make sure the X coordinate for that node point is close to 15ft but not less than 15 ft. Note the X node coordinate. In the case of this file, the node coordinate is ft. 6. Draw a window on the node point as shown in Figure 2. 74

75 Figure 2: Draw a drag window to select multiple nodes 7. Select the View->View Selected Objects Only menu command. 8. Click the Isometric View ( ) icon. Two nodes will appear in the graphics. 9. Select the first node using the Nodes cursor ( ). 10. The information for the selected node will be displayed in the Nodes table on the right hand side. 11. Change the X coordinate of the selected node to 15 as shown in Figure Repeat this Step 11 for the other node. 75

76 Figure 3: Draw a drag window to select multiple nodes 13. Select the View->Whole Structure menu command. Figure 4: Right hand side support beams are selected 14. The right supports need to be moved to x = 15 ft location from the x = 21 ft location. 15. You could select these right hand side supports and group them together. In the case of the My Bridge_2.std file, a right_support beam group has been created. 76

77 Figure 5: RIGHT_SUPPORT group name 16. Click on Select->By Group Name menu command. Select the Right_Support group name and you will note that the beams will be highlighted in the STAAD.Pro graphics window. 17. If you choose to move the supports by a distance of -6ft without moving the nodes to 15ft, you will note that additional nodes will be formed on the physical beams. The physical beams will have to be created again. Rather than doing this, we have manually moved the existing nodes near x=15 (i.e. could be x=15.19, 51.21) to x= Right click in the STAAD.Pro graphics window and select the Move command. 19. The Move dialog box will appear. Type in -6 ft in the Move Entities dialog box as shown in Figure 6. 77

78 Figure 6: Move command 20. Click on the Ok button and click on the Ok button on the dialog box that will appear. Click on the Yes button. 21. The list of duplicate nodes will be displayed. Click on each entry and press the Merge>> followed by OK and OK buttons. 22. Click the Close button. 23. This operation will more the right support by 6 ft to the left and also merge the duplicate nodes for the user. 24. Select and delete the beams shown in Figure 7. 78

79 Figure 7: Members to be deleted 25. Click on Geometry->Add Beam->Add Beam by Perpendicular Intersection and create the beams as illustrated in Figure 8. Figure 8: Members to be added 79

80 26. Select and delete the beams shown in Figure 9. Figure 9: Delete Beams 27. Click on Geometry->Add Beam->Add Beam from Point to Point menu command. 28. Create the beams as shown in Figure 10. Figure 10: Add Beams 80

81 29. Now that you have learned about property assignment, assign property reference 2 to the members highlighted in Figure 11. Figure 11: Property Assignment 30. Assign property reference 1 to the members highlighted in Figure12. 81

82 Figure 12: Property Assignment. 82

83 Exercise 10: Creating Load Cases & Items 1. Open the My Bridge_3.std if you were not able to complete the previous exercises. 2. Click on the General->Loads & Definition control tab on the left. 3. Click on the Load Cases Details tree item on the right. Three load cases have to be created. 4. Click on the Add button in the Load & Definitions dialog box on the right. The Add New: Load Cases dialog box will appear as shown in Figure 1. Figure 1: Add New: Load Cases dialog box 5. Enter L1=8.8 FT AND L2=1.1 FT in the Title text input box as shown in Figure 1. Press the Add button. 6. Press the Close button. We will now attempt to add the selfweight load 7. Select the L1=8.8 FT AND L2=1.1 FT title in the Load Cases Details tree item on the right. 8. The Add New: Load Items dialog box will appear as shown in Figure 2. Figure 2: Selfweight Definition 9. Select the inputs as shown in Figure 2 and press the Add button. 83

84 10. As a result, the load item should have SELFWEIGHT Y -1 included. 11. Select the SELFWEIGHT Y -1 item and select the Assign to View option. 12. Press the Assign button. We will now attempt to add the test loads as distributed loads. 13. Select the L1=8.8 FT AND L2=1.1 FT title in the Load Cases Details tree item on the right. 14. Select the Toggle Physical Member mode as shown in Figure Select the Add button in the Data Area. Figure 3: Selfweight Definition 16. Select the Physical Member Load->Uniform Load item in the Add New: Load Items dialog box. Figure 4: Add New: Load Items dialog box 17. Input the parameters as shown in Figure Click the Add button. 19. Input the parameters as shown in Figure Click the Add button. 84

85 Figure 5: Add New: Load Items dialog box 21. Click the Close button. 22. Select the UNI GY command in the data area. 23. Select the physical member cursor ( ). 24. Rubberband the entire bridge structure. 25. The physical members will be highlighted as shown in Figure 6. Figure 6: Physical beam members are highlighted 85

86 26. Select the Assign To View option and click the Assign button. 27. Select the UNI GY command in the data area. 28. Select the Assign To View option and click the Assign button. Due to a refreshing problem in STAAD.Pro, the loads may not appear as shown in Figure 7. Simply close and re-open the model to see the loads as shown in Figure 7. You will need to click on General control tab and then select Load Case Details-> L=0 VLT PRELOAD->UNY GY to see the loading. Figure 7: Physical beam members are loaded 29. Create the other seventeen load cases as shown in Table 1 and Figure 8. Figure 8: Seventeen more load cases are created 86

87 30. Click on the Load Cases Details tree item on the right. Three load cases have to be created. 31. Click on the Add button in the Load & Definitions dialog box on the right. 32. Enter Weight in the Title text input box. Press the Add button. 33. Press the Close button. We will now attempt to add the selfweight load 34. Select the Weight of the Structure title in the Load Cases Details tree item on the right. 35. The Add New: Load Items dialog box will appear. 36. Select the inputs as shown in Figure 2 and press the Add button. 37. As a result, the load item should have SELFWEIGHT Y -1 included. Select the SELFWEIGHT Y -1 command. 38. Select the Assign to View option. 39. Click the Assign button. Click the Ok button on the confirmation dialog box. 40. Click on the Load Cases Details tree item on the right. 41. Click on the Add button in the Load & Definitions dialog box on the right. 42. Enter Lateral Load in the Title text input box. Press the Add button. 43. Press the Close button. We will now attempt to add the selfweight load 44. Select the Lateral Load title in the Load Cases Details tree item on the right. 45. Click the Add button. 46. The Add New: Load Items dialog box will appear. 47. Select the inputs as shown in Figure 2 and press the Add button. 48. As a result, the load item should have SELFWEIGHT Y -1 included. Select the SELFWEIGHT Y -1 command. 49. Click the Assign button. Click the Ok button on the confirmation dialog box. 50. Select the Lateral Load title in the Load Cases Details tree item on the right. 51. Click the Add button. 52. The Add New: Load Items dialog box will appear. 87

88 53. Select the Physical Member Load->Uniform Load item in the Add New: Load Items dialog box. Figure 9: Add New: Load Items dialog box 54. Input the parameters as shown in Figure Click the Add button. 56. Select the Physical Member Load->Concentrated Force item in the Add New: Load Items dialog box. 57. Input the parameters as shown in Figure Click the Add button. 59. Press the Close button. 60. Select the physical member cursor ( ). 61. Select the UNI GY command in the data area in the last load case. 62. Select the Use Cursor to Assign option and click on the two physical beams as illustrated in Figure

89 Figure 10: Add New: Load Items dialog box Figure 11: Physical Beams to which loads have to be assigned using Use Cursor to Assign option 63. Select the physical member cursor ( ). 64. Select the CON GZ command in the data area in the last load case. 65. Select the Use Cursor to Assign option and click on the physical beam as illustrated in Figure

90 Figure 12: Physical beam to which concentrated lateral load have to be assigned using Use Cursor to Assign option 90

91 Exercise 11: Performing Analysis 1. Open the My Bridge_4.std file if you did not follow the previous exercises. 2. Click on Analysis/Print control tab on the left. The Analysis/Print Commands dialog box will appear. 3. Select the All option in the Perform Analysis tab and press the Add button. Figure 1: The Analysis/Print Commands dialog box 4. Click the Close button. 5. Click on Analyze->Run Analysis command. The STAAD Analysis and Design dialog box will appear. 6. You should not have zero errors in the STAAD Analysis and Design dialog box. 7. Select the Go To Post Processing Mode option button and click on the OK button. 91

92 Exercise 12: Understanding the Results 1. Open the My Bridge_5.std file if you have not followed the above exercises. Note: If you are not using the My Bridge_5.std file, you will have to create a group of beams that represent the cantilever bridge section. You may just call the beam group Cantilever. 2. Click on Analyze->Run Analysis command. The STAAD Analysis and Design dialog box will appear. 3. You should not have zero errors in the STAAD Analysis and Design dialog box. 4. Select the Go To Post Processing Mode option button and click on the OK button. 5. Select the Node->Displacement tab. The displacement of each and every node can be determined by simply clicking on a node point in the graphics window and looking at the displacement table on the right. Figure 1: Displacements Lateral Load Case 92

93 6. Click on the Summary tab in the Node Displacements table on the right. Note the Min Y displacement row. The Min Y displacement represents the max ve displacement in the structure for all load cases. If you highlight the Min Y row, you will see the node with max ve displacement highlighted in the graphics window. Figure 2: Maximum Y Displacement 7. Let us say that the maximum displacement for the cantilever section is to be determined. The STAAD.Pro user can data filtering options provided with these tables. Right click on the Node Displacements table on the right. 8. Select Results Setup option. 9. Click on the Range tab. 10. Select the Group option. 11. Select G2:_Cantiliver as shown in Figure 3. 93

94 Figure 3: Results Setup 12. Click on the Ok button. 13. You will see that the Summary tab has now been updated. The max ve displacement is now reported for the cantilever section of the bridge as shown in Figure 4. Figure 4: Results Setup 94

95 14. Select the Node->Reactions tab. The support reaction of each and every support node can be determined by simply clicking on a node point in the graphics window and looking at the support reaction table on the right. Note: Make sure that the Difference row for each load case in the Statics Check Results window is close to zero. A non-zero value usually indicates instability in the structure. You may use the 0.99 MPX 0.99 MPY 0.99 MPZ at the joints to avoid using a completely released joint. Note that in this example, instability is reported at certain joints. For example, a joint at which four truss members are framing together and lie in the same plane. This problem can be solved by designing the connections to take moments, providing extra truss members connecting at that joint, or using partial moment release. Figure 5: Support Reactions 15. Select the Beam->Forces tab. The bending moment diagram will be displayed. The user may turn on the deflection and loading diagrams using the icons. 95

96 Figure 6: Beam end and section forces Figure 7: Moment, deflection and load diagram 96

97 16. The tables on the right show the forces for each beam member in the model. Right click on this table and select the Results Setup option. 17. You may specify which load case, member or group results need to be displayed. Figure 8: Result sorting tool 18. Select the Beam->Stresses tab. The combined axial stress distribution diagram can be seen for any member. 97

98 Figure 9: Combined axial and bending stress distribution diagram 19. Select the Beam->Graphs tab. The moment, shear, and axial force diagram can be seen for any member. 98

99 20. Click on the Modeling tab. Figure 10: Moment, shear, and axial force diagram 21. Right click in the graphical user interface and select Labels. Suppose you wanted to see the members that had a combined axial and bending stress of 500 psi. 22. Select the Force Limits tab and provide the inputs as shown in Figure Click on the Apply button. The beams shown in red in Figure 12 have exceeded the combined axial and bending stress of 500 psi. 24. This procedure can be used to find which members are exceeding say a 30 ksi criteria. 99

100 Figure 11: Force Limits 100

101 Figure 12: Combined axial and bending stress contour Experiment with the model and try changing some of the truss connections to partial moment releases. Try changing the section sizes of the members. 101

102 Exercise 13: Design of the Structure using AISC Note: STAAD.Pro cannot perform code checking on square prismatic steel sections defined in this model. The user could define a general section or create a tube section using the section database to perform the code checking as per the AISC code. 1. Open the My Bridge_6.std file if you have not followed the exercise above. 2. Click on Design->Steel control tab on the left. 3. Select the AISC code in the Current Code selection box in the data area. 4. Click the Define Parameters button in the data area. The Design Parameters dialog box will appear as shown in Figure Select the FYLD design parameter and enter and assign the yield strength of steel to be used for the bridge if not 36 ksi. In the case of this tutorial, the yield strength (i.e. 50 ksi) will be used. Input the value of 7200 kip/ft2 and press the Add button. 6. Select the Method parameter and select the LRFD code. 7. Click on the Add button. 8. Click on the Close button. 9. Assign the FYLD parameters to the view. 10. Click the Commands button. The Design Commands dialog box will appear. 11. Select the Check Code command and press the Add button 12. Assign the Check Code command to all members. Figure 1: The Design Parameters dialog box 13. Click on Analyze->Run Analysis command. The STAAD Analysis and Design dialog box will appear. 102

103 14. You should not have zero errors in the STAAD Analysis and Design dialog box. 15. Select the Go To Post Processing Mode option button and click on the OK button. 16. In the Postprocessing mode->beam->unity Check, you will note the check code results as shown in Figure Right click in the graphics and select Labels->Design Results. 18. Uncheck the Show Values check box. 19. You may provide your own color coding in this dialog box. Any member over a unity/design ratio ratio of 1 will be colored in green by default. 20. Click the Ok button in the Diagrams dialog box. 103

104 Figure 2: Design results 21. The members shown in red and blue have failed. There are other design parameters that the user should look at. For example, look at the information provided in Appendix D of this manual. 22. You may have to check for the capacity of the connection using the AISC code. The following calculation can be used. V r = s n m A s F u s = Factored shear resistance = 0.67 A s = Cross section area of bolt = π/4 (d 2 ) = π/4 (0.3 2 ) = in 2 n = Number of bolts = 2 m = Number of shear planes = 2 A b = Cross section of bolt = 0.3 Fu = Bolt tensile strength = 150 kips/in 2 V r =0.67 x 2 x 2 x x 150 = 28.5 kips Max Tension = 2 Kips (From STAAD.Pro) < 28.5 Kips 104

105 4.0 STAAD.Pro and Structural Modeler Integration The bridge frame could first be constructed and analyzed using STAAD.Pro. After the analysis and design has been finalized, the 3D model can be exported to Structural Modeler for drawing generation. Structural Modeler is an advanced drawing generation and 3D modeling software that will allow the engineer to generate floor plans, sections, and elevations using an existing STAAD.Pro model. The entire 3D model is stored in Structural Modeler along with the different elevations, plans, and sections that the user has requested. Structural Modeler also keeps track of materials, quantities, cost reports, and specifications, all automatically tracked within the design file. Plans, sections, elevations, bills of materials - all are stored or linked to the 3D model, so any changes made to the design file will automatically update the reports and drawings. 105

106 1. Launch Structural Modeler. 2. Set the User to Structural, Project to Structural_Imperial, and Interface to default. 3. A new Structural Modeler File. In the File Open dialog box, click the New File icon ( ). 4. Select an appropriate folder and type the file name Bridge_Model. 5. Click on the Save button. 6. Select the Bridge Model.dgn file and click the Open button. The Structural Modeler GUI will open as shown in Figure Select the Settings->Design File menu command and set the Master Unit to Meters in the Working Units section. 8. Click the Ok button Figure 1: Structural Modeler Graphical User Interface 106

107 Hint: You can change the background color from black to white using the Workspace- >Preferences->View Options->Black Background -> White menu command. 9. Make sure that the Structural->Analytical Features menu command is checked on. 10. Import the bridge frame STAAD.Pro model into Structural Modeler using the Structural Analytical->Data Exchange->Analysis Import control tab on your left. 11. The Import From Analysis Program dialog box will appear as shown in Figure 2. Figure 2: Import from Analysis Program dialog box. Note the Map Section Names option in the Import from Analysis Program dialog box. This box contains a link to the mapping file for the AISC sections. AISC sections will most probably not be used for the bridges in constructed by most students. Hence, we will need to first create the section in the Structural Modeler Database and then create a mapping of the sections used in STAAD.Pro with the sections in Structural Modeler. The following directory will usually contain the section profiles: C:\Documents and Settings\All Users\Application Data\Bentley\MicroStation V8i (SELECTseries 1)\WorkSpace\TriForma\tf_imperial\data 12. The us.xml file is the one used the most. You could easily find the xml file used on your machine by simply clicking on Structural Physical->Steel Column > Primary tab on the left. 13. The Place Steel Column dialog box will appear. As shown below. 107

108 Figure 3: Place Column dialog box. 14. Press the magnifying glass icon as shown above. The Structural Sections dialog box will appear as shown in Figure 4. Figure 4: Section Database. 108

109 15. Select the File->Open menu command. The Section File Manager box will appear as shown below. Figure 5: Section File Manager 16. Hoover your mouse cursor over the Section Files seen at the bottom of the dialog box and you will notice the name and location of the xml file being used for your installation. The *.xml version of a section file format is a true XML file. In XML files, commands are written as open and close statements. If a command is opened but not closed, it could keep the entire file from being usable. The following shows an example of lines in the us.xml file: Figure 6: XML Text 109

110 You can see in this small section that the first line starts with <I-Shape. This opens a definition of a shape of an I-beam. The way the dimensions and properties are written follows the requirements for this XML file. Note that everything that is opened is also closed, often with the same phrase (such as I-Shape), but with a slash in front of it, such as </I-Shape>. If you open the us.xml file in Notepad, you could make all sorts of changes that may not follow the protocol of an XML file. These changes could render it useless. To edit your XML files, you should use an XML editor rather than a text editor. Structural Modeler delivers a Microsoft Excel spreadsheet, StructuralShapesTemplate.xls, that you can use to edit your file. The StructuralShapesTemplate.xls spreadsheet is a template that lets you load the XML file you want to edit (such as us.xml), make your changes while working in Microsoft Excel, and then export the changes to the XML file. The exported data is applied to the XML file properly, and you maintain the integrity of the XML format. This file is located at the following location: C:\Documents and Settings\All Users\Application Data\Bentley\MicroStation V8i (SELECTseries 1)\WorkSpace\TriForma\tf_imperial\data 17. Open this file using Microsoft Excel. 18. Select the Rectangular Hollows sheet and input the following sections (The parameters provided in this example are not realistic): name d thickness width W A HSS-1/2X1/2X1/ HSS-1X1X1/ HSS-1-1/2X1-1/2X1/ Ix Iy Sx Sy Figure 7: XML file creation to store custom shapes 110

111 19. Save this file as a CUSTOM.xml at the following location: C:\Documents and Settings\All Users\Application Data\Bentley\MicroStation V8i (SELECTseries 1)\WorkSpace\TriForma\tf_imperial\data Figure 8: Saving XML files using Excel 20. Close Excel. 21. In the section file manager choose the CUSTOM.xml file. You will note that the file name will appear in the Section Files area of the Section File Manger dialog box. 111

112 Figure 9: Referencing Custom sections in Structural Modeler 22. The sections defined in the CUSTOM.xml file will be available for your use. Click on the Done button. 23. Select Rectangular Tubes in the Type selection box. You will note that the custom sections will appear in the Structural Sections dialog box. Figure 10: Custom sections in Structural Modeler 112

113 We need to inform Structural Modeler about the STAAD.Pro to Structural Modeler Mapping. 24. Create a simple notepad or text file with the following inputs for example: W44X335 W44X335 ST HSS-1/2X1/2X1/32 W21X44 ST HSS-1X1X1/32 W14X38 ST HSS-1-1/2X1-1/2X1/32 W4X13 ST PIPE2STD PIPS20 PIPE Save this mapping file at the following location: C:\Documents and Settings\All Users\Application Data\Bentley\MicroStation V8i (SELECTseries 1)\WorkSpace\TriForma\tf_imperial\data as bridge_mapping_file.txt 25. Open the My Bridge_7.std STAAD input file using notepad. 26. Save this file as My Bridge_8.std. Note: Make sure the extension of the file is set to std. If the save as type is not set to All Files, txt extension will be added by default. 113

114 27. Change the following set of lines from: MEMBER PROPERTY AMERICAN 9 11 TO TO TO TO TO TO TO TO TO TO TABLE ST TUBE TH WT DT TO TO TO TO TO TO TO TABLE ST TUBE TH WT DT TABLE ST TUBE TH WT DT TO 38 TABLE ST PIPS20 To: MEMBER PROPERTY AMERICAN 9 11 TO TO TO TO TO TO TO TO TO TO TABLE ST W21X TO TO TO TO TO TO TO TABLE ST W14X TABLE ST W4X13 35 TO 38 TABLE ST PIPS20 Delete all lines after this line except the FINISH line. 28. Save the file. 29. In Structural Modeler select STAAD.Pro as the Analysis program to import from. 30. Select the appropriate file name by pressing the button. The file name is My_Bridge_8.std in the case of this exercise. 31. Set the mapping file name to bridge_mapping_file.txt. Check the Map Section Names check box. 32. Select the Import Options tab and enter the following information. 114

115 Figure 11: Import from Analysis Program dialog box. 33. This dialog box allows the user to select a family and part name to the vertical and horizontal members. 34. Click the Import button. The beam property mapping table will be displayed in the Update Design Results box. 35. Click on the Update button. 36. The bridge model will be displayed in Structural Modeler as shown in Figure

116 Figure 12: STAAD.Pro Model Exported to Structural Modeler. 37. Once the 3D Model is placed in Structural Modeler, the Plans, Elevations, and section drawings can be produced using the Drawing Extraction Manager and the Referenced Drawings features. Figure 13: STAAD.Pro Model Exported to Structural Modeler. 116

117 Figure 14: Structural Modeler drawing Generation. 117

118 5.0 Help, Questions, Comments There is a lot of help available for STAAD.Pro in electronic format. You may also contact Ravi Ozarker at Ravi.Ozarker@bentley.com for any other questions or call Ext

119 Finally. Thank you for using Bentley Products and Wish You all the best! 119

120 APPENDIX A CREATING BRIDGE GEOMETRY USING STAAD.PRO V8I GRID SYSTEM 120

121 1. The goal of the next few steps is to draw the stick model of the bridge structure using the STAAD.Pro V8i drawing grid system. 2. Click the Geometry control tab on the left hand side. On the right hand side of your screen, you should see a Snap Node/Beam dialog box. If you do not see this dialog box, you may view this by simply clicking on Geometry->Snap/Grid Node->Beam menu item. Figure A1: Snap/Node Beam dialog box 3. Click on the Create button. 4. The Grid Definition dialog box will appear as shown in Figure A2. 121

122 Figure A2: Grid definition dialog box 5. Input the grid creation parameters as shown in Figure A2. 6. Click the Ok button. 7. The Linear entry will appear in the Snap/Node Beam dialog box. Check the Linear entry and you will notice that the linear grid will appear in the STAAD.Pro graphics window. Figure A3: Grid Creation 122

123 8. Click the Snap/Node/Beam button and create the grillage of beams as shown in Figure A4. Figure A4: Grid Creation 9. Click the Snap/Node/Beam button and create the grillage of beams as shown in Figure A Select the Beams Cursor from the left hand side. Figure A4: Beams Cursor 11. Select all the beams in the graphics window. Ctrl + A will select all the beams in the model. 12. Click on Geometry->Translational repeat command. The 3D Repeat dialog box will appear as shown in Figure A5. 123

124 Figure A5: 3D Repeat dialog box 13. Input the 3D Repeat parameters as shown in Figure A Click the OK button. The bridge geometry will be created as shown in Figure A6. Figure A6: Translational Repeat 15. Create the vertical diagonal members using the Geometry->Add Beam->Add Beam From Point to Point menu command. 124

125 Figure A7: Vertical diagonals created using the Geometry->Add Beams menu command 16. Click the Snap/Node/Beam button and create the grillage of beams as shown in Figure A4. 125

126 APPENDIX B CREATING BRIDGE GEOMETRY USING STAAD.PRO V8I DXF IMPORT 126

127 1. Open MicroStation XM. 2. Open the DGN_Example.dgn file distributed with this tutorial. Figure B1: Elliptical Base Bridge stick model constructed in MicroStation 3. Click on file File->Export->DGN, DWG, DXF. The Export File dialog box will appear as shown in Figure B2. 4. Select the dxf export option as shown in Figure B2. 127

128 Figure B2: The Export File dialog box in Microstation 5. Select an appropriate location to save the dxf file. Click the Save button. 6. Close MicroStation. 7. Launch STAAD.Pro by clicking on the Start->All Programs->STAAD.Pro V8i->STAAD.Pro icon. The STAAD.Pro V8i introduction screen will appear. 8. Click on the File->New menu command. The New dialog box will appear. 9. Provide the model options as shown in Figure B3. Figure B3: The New Dialog box 128

129 10. Click on the Next button. The Where do you want to go Today? Dialog box will appear as shown in Figure B Click on the Finish button. 12. The STAAD.Pro V8i user interface will appear as shown in Figure B5. Figure B4: The Where do you want to go Today? dialog box 129

130 Figure B5: STAAD.Pro User Interface 13. Click on File->Import menu command. The Import dialog box will appear as shown in Figure B6. Figure B6: The Import dialog box 14. Select the 3D DXF import option and click the Import button. 15. The Open dialog box will appear. Select the DGN_Example.dxf file which was created in Step Click on the Open button. The DXF Import dialog box will appear as shown in Figure B7. 130

131 Figure B7: The Import dialog box 17. Select the Y Up option. The Y Axis should be the axis of gravity in your STAAD.Pro models. 18. Click on the OK button. The Set Current Input Units box will appear. The MicroStation file was created using the foot unit system. Select Foot and KiloPound in the Set Current Input Units box and press the OK button. The bridge geometry will appear as shown in Figure B8. Figure B7: The Import dialog box 131

132 Figure B8: Bridge Frame Imported from MicroStation 19. Delete the unwanted lines as highlighted in Red in Figure B8. The STAAD.Pro user must check if the imported model is ok from a structural analysis point of view. The Tools menu command is very useful for checking structural integrity of the imported stick model. For more information about dxf import/export please refer to the whitepaper on the following link: ftp://ftp2.bentley.com/dist/collateral/web/building/staadpro/dxf_import_into_staad_pro.pdf 20. Click the Snap/Node/Beam button and create the grillage of beams as shown in Figure A Select the Beams Cursor from the left hand side. Figure B9: Beams Cursor 22. Select all the beams in the graphics window. Ctrl + A will select all the beams in the model. 23. Click on Geometry->Translational repeat command. The 3D Repeat dialog box will appear as shown in Figure B

133 Figure B10: 3D Repeat dialog box 24. Input the 3D Repeat parameters as shown in Figure B Click the OK button. The bridge geometry will be created as shown in Figure B11. Figure B11: Translational Repeat 133

134 APPENDIX C STAAD.PRO INPUT COMMAND FILE 134

135 You may copy the following text into the STAAD.Pro editor to view this model in STAAD.Pro To Launch the STAAD.Pro editor click on Edit->Edit Input Command File menu command. Replace the text in the editor with the following text. 135

136 STAAD SPACE START JOB INFORMATION ENGINEER DATE 10-Sep-09 END JOB INFORMATION INPUT WIDTH 79 UNIT FEET KIP JOINT COORDINATES ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; 136

137 ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; MEMBER INCIDENCES ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; 137

138 ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; 138

139 ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; DEFINE PMEMBER TO TO PMEMBER TO TO PMEMBER TO TO

140 PMEMBER TO TO PMEMBER 4 START GROUP DEFINITION MEMBER _RIGHT_SUPPORT TO _CANTILIVER TO TO TO TO TO TO TO JOINT END GROUP DEFINITION MEMBER OFFSET 14 TO TO TO TO TO TO TO TO TO TO 362 START TO TO TO TO TO TO TO TO TO TO 362 END TO TO TO 354 START TO TO TO 354 END END START DEFINE MATERIAL START ISOTROPIC STEEL E 4.176e+006 POISSON 0.3 DENSITY ALPHA 6e-006 DAMP 0.03 ISOTROPIC CONCRETE E POISSON

141 DENSITY ALPHA 5e-006 DAMP 0.05 END DEFINE MATERIAL MEMBER PROPERTY AMERICAN 9 11 TO TO TO TO TO TO TO TO TO TO TABLE ST TUBE TH WT DT TO TO TO TO TO TO TO TABLE ST TUBE TH WT DT TABLE ST TUBE TH WT DT TO 38 TABLE ST PIPS20 CONSTANTS MATERIAL STEEL ALL SUPPORTS PINNED MEMBER RELEASE 7 TO TO START MPX 0.99 MPY 0.99 MPZ TO TO END MPX 0.99 MPY 0.99 MPZ 0.99 LOAD 1 LOADTYPE None TITLE L=0 VLT PRELOAD SELFWEIGHT Y -1 PMEMBER LOAD 1 TO 4 UNI GY TO 4 UNI GY LOAD 2 LOADTYPE None TITLE L=0 VLT STEP 1 SELFWEIGHT Y -1 PMEMBER LOAD 141

142 1 TO 4 UNI GY TO 4 UNI GY *** LOAD 3 LOADTYPE None TITLE L=0 VLT STEP 2 SELFWEIGHT Y -1 PMEMBER LOAD 1 TO 4 UNI GY TO 4 UNI GY *** LOAD 4 LOADTYPE None TITLE L=3 VLT PRELOAD SELFWEIGHT Y -1 PMEMBER LOAD 1 TO 4 UNI GY TO 4 UNI GY *** LOAD 5 LOADTYPE None TITLE L=3 VLT STEP 1 SELFWEIGHT Y -1 PMEMBER LOAD 1 TO 4 UNI GY TO 4 UNI GY *** LOAD 6 LOADTYPE None TITLE L=3 VLT STEP 2 SELFWEIGHT Y -1 PMEMBER LOAD 1 TO 4 UNI GY TO 4 UNI GY *** LOAD 7 LOADTYPE None TITLE L=6 VLT PRELOAD SELFWEIGHT Y -1 PMEMBER LOAD 142

143 1 TO 4 UNI GY TO 4 UNI GY *** LOAD 8 LOADTYPE None TITLE L=6 VLT STEP 1 SELFWEIGHT Y -1 PMEMBER LOAD 1 TO 4 UNI GY TO 4 UNI GY *** LOAD 9 LOADTYPE None TITLE L=6 VLT STEP 2 SELFWEIGHT Y -1 PMEMBER LOAD 1 TO 4 UNI GY TO 4 UNI GY *** LOAD 10 LOADTYPE None TITLE L=7 VLT PRELOAD SELFWEIGHT Y -1 PMEMBER LOAD 1 TO 4 UNI GY TO 4 UNI GY *** LOAD 11 LOADTYPE None TITLE L=7 VLT STEP 1 SELFWEIGHT Y -1 PMEMBER LOAD 1 TO 4 UNI GY TO 4 UNI GY *** LOAD 12 LOADTYPE None TITLE L=7 VLT STEP 2 SELFWEIGHT Y -1 PMEMBER LOAD 143

144 1 TO 4 UNI GY TO 4 UNI GY *** LOAD 13 LOADTYPE None TITLE L=9 VLT PRELOAD SELFWEIGHT Y -1 PMEMBER LOAD 1 TO 4 UNI GY TO 4 UNI GY *** LOAD 14 LOADTYPE None TITLE L=9 VLT STEP 1 SELFWEIGHT Y -1 PMEMBER LOAD 1 TO 4 UNI GY TO 4 UNI GY *** LOAD 15 LOADTYPE None TITLE L=9 VLT STEP 2 SELFWEIGHT Y -1 PMEMBER LOAD 1 TO 4 UNI GY TO 4 UNI GY *** LOAD 16 LOADTYPE None TITLE L=12 VLT PRELOAD SELFWEIGHT Y -1 PMEMBER LOAD 1 TO 4 UNI GY TO 4 UNI GY *** LOAD 17 LOADTYPE None TITLE L=12 VLT STEP 1 SELFWEIGHT Y -1 PMEMBER LOAD 144

145 1 TO 4 UNI GY TO 4 UNI GY *** LOAD 18 LOADTYPE None TITLE L=12 VLT STEP 2 SELFWEIGHT Y -1 PMEMBER LOAD 1 TO 4 UNI GY TO 4 UNI GY *** LOAD 19 LOADTYPE None TITLE WEIGHT SELFWEIGHT Y -1 *** LOAD 20 LOADTYPE None TITLE LATERAL LOAD SELFWEIGHT Y -1 PMEMBER LOAD 3 4 UNI GY CON GZ PERFORM ANALYSIS PRINT ALL PARAMETER 1 CODE AISC UNIFIED FYLD 7200 ALL METHOD LRFD CHECK CODE ALL FINISH 145

146 APPENDIX D SPECIFYING PROPER SLENDERNESS LENGTHS IN STAAD.PRO 146

147 1.0 Introduction STAAD.Pro is a general purpose structural analysis and design tool. The structural engineer may also first create the steel frame models in STAAD.Pro and design then design the steel frames using the appropriate loading and codes. The purpose of this document is to demonstrate the use of the LY and LZ design parameters in STAAD.Pro. 147

148 2.0 Slenderness Lengths Following figure shows four identical members attached to a steel frame. One of t he bays has secondary beam s (i.e. the rear bay). The re maining two bays have secondary beam s but the engineer did not model those intermediate beams in this model (e.g. bay at the front). Figure 1: Steel tubes (Identical Members) attached to a steel frame There is no force directly applied to the identical members. The structure is symmetric and loads are symmetric also. One would expect either all the four members to pass or all four to fail. Figure 2: Code Check results 148

149 The engineer perform ed a code check using the AISC code on the entire fra me and obtained the results shown in Figure 2. Note that two of the four identical members at the f ront fail with a design ratio of Th e two identical m embers at the re ar end of the structure have very low unity ratios. The beams at the front failed in STAAD.Pro due to slenderness limitations and effective length or Section E2 of the AISC code. Let us look at the results for the front identical member. * 40 ST TUB20203 (AISC SECTIONS) FAIL Clause E C SECTION CLASS: CB: SLENDERNESS CHECK: ACTUAL RATIO: ALLOWABLE RATIO: SECTION CAPACITIES: (UNIT - KIP FEET) AX.TENS: 0.00E+00 COMPRESS:0.00E+00 TORSION: 0.00E+00 BEND. Z: 0.00E+00 BEND. Y: 0.00E+00 SHEAR Z: 0.00E+00 SHEAR Y: 0.00E SECTION PROPERTIES: (UNIT - FEET) AXX: 0.01 AYY: 0.01 AZZ: 0.01 RZZ: 0.06 RYY: 0.06 SZZ: 0.00 SYY: PARAMETER: (UNIT - KIP FEET) KL/R-Z: KL/R-Y: UNL: 4.7 CB: 0.00 FYLD: FU: NET SECTION FACTOR: 1.00 SHEAR LAG FACTOR: 1.00 STP: 1 DFF: 0.00 dff: CRITICAL LOADS FOR EACH CLAUSE CHECK (UNITS KIP -FEET) CLAUSE RATIO LOAD FX VY VZ MZ MY Cl.D E Cl.E E Cl.F-Major E+00 - Cl.F-Minor E+00 Cl.H1/H E E+00 Cl.G-Major E Cl.G-Minor E Cl.H E E E E E ERROR : CALCULATED SLENDERNESS RATIO EXCEEDS ALLOWABLE LIMIT. The beams at the fron t should have passed but faile d due to slenderness because the KL/r of the beam exceeds the allowable slenderness value of 200. The slenderness length (i.e. Lx in KLx/rx or Lz in KLz/rz) value is the member length in STAAD.Pro by default. Engineers have to check if the member length is the slenderness length based on how the structure has been modeled. In this case, the two identical members at the rear end of the st ructure have a LZ and LY of 4.71 ft. Using the infor mation presented in F igure 3 belo w, the slenderness length m ay be 4.71 for LY but LZ should be ft. This is because there is no restraint along the Local Y axis. 149

150 Figure 3: Lz or Slenderness length about local z axis (out of the plane of the slope) In the case of the two identical beams at the front, you will note that we have not modeled the secondary beams. In this case, the LY (Slenderness length about the local Y axis as shown in Figure 5) should be set to 4.17 ft. 150

151 Figure 4: Slenderness lengths can be specified in STAAD.Pro as Design Parameters Figure 5: Ly or Slenderness length about local y axis (in the plane of the slope) 151

152 After implementing these changes, you will note that the four identical beams have identical design ratios of Figure 6: Updated Code Check results The user may use STAAD.Pro s Interactive Steel Designer to estimate the values of LX, LY, and LZ, however engineering judgment is required in this case also. Figure 7 shows how the LY and LZ calculated by the Interactive Steel Designer may not be correct. The LY for physical members M3 and M4 should be 4.71 ft. 152

153 Figure 7: Formation of Physical Members in STAAD.Pro 153

154 APPENDIX E DATASET INSTALLATION 154

155 Dataset Installation: Attached is the Structural Analysis, Design, And Drawing Production docum ent prepared for participants of this year s AISC 2013 Student S teel Bridge Com petition. This year datas et zip file STUDENT_STEEL_BRIDGE_COMPETI TION_2013_DATASETS_BENTLEY.zip is also distributed with the manual. The manual has thirteen step-by-step exercises. 1. Unzip the contents of the zip file to a location on your computer (e.g. c:\training). You could use winzip to see/unzip the contents or you could simply right click on the file and click on explore. 2. Let us assume that you right click on the file and select Explore. Windows Explorer will appear as shown below. 3. Copy the folder inside the zip file to a safe location on your machine. 4. The STUDENT_STEEL_BRIDGE_COMPETITION_2013_DATASETS_BENTLEY folder contains three sub-folders. i ii Microstation Contains a dxf file for Appendix A STAAD.Pro Contains nine STAAD.Pro models. My Bridge_1.std which contains results of following Ex. 1 to 7 in the m This file can be used for Ex. 8. My Bridge_2.std which contains results of following Ex. 1 to 8 in the m This file can be used for Ex. 9. My Bridge_3.std which contains results of following Ex. 1 to 9 in the m This file can be used for Ex. 10. My Bridge_4.std which contains results of following Ex. 1 to 10 in the m This file can be used for Ex. 11. My Bridge_5.std which contains results of following Ex. 1 to 11 in the m This file can be used for Ex anual. anual. anual. anual. anual.