Steel Construction

Features

• Diaphragm Constraint

• Design Optimization

• Automatic Area Mesh

• Mode Shapes

• New Model (not from template, started from scratch)

• Linear Replication

• Mirror Replication

• Radial Replication

• Steel Design

1. Click the File menu > New Model command to displays the New Model form.

2. Click the drop-down box to set the units to .

3. Click the Blank button .

4. Click the Define menu > Coordinate Systems/Grids command to display the Coordinate/Grid Systems form.

5. In that form click on the Modify/Show System button to display the Define Grid Data form. Fill in the form as shown in Figure C-1. Type values in the Grid ID and Ordinate cells; click in the Line Type, Visibility, and Bubble Loc. cells until the appropriate option appears:

• Click the OK buttons on the Coordinate/Grid System Data and Coordinate/Grid Systems forms to exit the forms.

6. Click in the left window entitled 3-D View to make sure it is active. The window is highlighted when it is active.

7. Click the Set Default 3D View button to change to the default 3-d view.

8. Click in the right window entitled 3-D View to make sure it is active. Click the Set XZ View button to change the view to an X-Z elevation. Note that the title of the window changes to X-Z Plane @ Y=0.

9. Click the Quick Draw Frame/Cable/Tendon button or click the Draw menu > Quick Draw Frame/Cable/Tendon command to display the Properties of Object form. By default, the Line Object Type should be Straight Frame. If it is not, click in that box to display the drop-down list and click on Straight Frame to select it. We will ignore the other property settings shown because other assignments will be made later in the modeling process.

10. Click on the grid line at the point labeled “A” in Figure C-2 to enter a frame object.

11. Click on the grid line at the point labeled “B” in Figure C-2 to enter another frame object

12. Click the Draw Frame/Cable/Tendon Element button or the Draw menu > Draw Frame/Cable/Tendon command to display the Properties of Object form. Again, be sure that the Line Object Type is Straight Frame. We will ignore the other property settings shown in the form because other assignments will be made later in the modeling process.

13. Click on the points labeled “C,” “D,” and “E” in Figure C-2, in that order, and then press the Enter key on the keyboard to draw two more frame objects.

14. Click on the point labeled “F” and then double click the point labeled “E” in Figure C-2 to draw the next frame object.

Note: You could have single-clicked the point labeled “E” in Figure C-2 and then pressed the Enter key on the keyboard to finish drawing the frame object.

15. Click on the point labeled “G” and then double click the point labeled “D” in Figure C-2 to draw the next frame object.

16. Click on the point labeled “D” and then double click the point labeled “F” in Figure C-2 to draw the next frame object.

17. Click the Set Select Mode button to exit Draw Mode and enter Select Mode.

18. Click the Set Display Options button (or the View menu > Set Display Options command) to display the Display Options for Active Window form. In that form:

• Check the Labels box in the Joints area.

• Check the Labels box in the Frames/Cables/Tendon area.

• Check the Fill Objects box.

• Click the OK button. The screen appears as shown in Figure C-3.

19. Click on line objects 1 and 3 to select them.
    Click the Edit menu > Divide Frames command to display the Divide Selected Frames form. Verify that this form is filled out as shown in the adjacent figure and click the OK button.

20. Click the Draw Frame/Cable/Tendon button or click the Draw menu > Draw Frame/Cable/Tendon command. Again, we can ignore the current property settings displayed in the Properties of Object form. As an alternate method, we could have defined the sections before drawing the frame objects, and then assigned the sections when drawing using the Properties of Objects form.

22. Draw frame objects by single clicking then double clicking on the joints identified in the following table:

Click on This Joint	Double Click on This Joint
9	13
8	12
7	11
6	10
13	2
12	9
11	8
10	7

23. Click the Set Select Mode button to exit Draw Mode and enter Select Mode.

24. Click in the Window labeled X-Z Plane @ Y=0 to activate it.

25. Click the Select All button to select all objects.

26. Click the Edit menu > Replicate command to display the Replicate form. In that form:

• Select the Mirror Tab.

• In the Mirror About Plane area select Parallel to Y.

• In the Intersection of Plane with XZ Plane area type 10.5 in the x1 edit box.

• Type 10.5 in the x2 edit box.

• Click the OK button to proceed with the replication.

27. Click the Draw Frame/Cable/Tendon Element button or the Draw menu > Draw Frame/Cable/Tendon command.

28. Click on joint 4 and then double click on joint 17 to draw a frame object.

Note: If the font size for the joint labels is too small, use the following procedure to increase the font size. Click the Options menu > Preferences > Dimensions/Tolerances command and type in a new (larger) font size in the Minimum Graphic Font Size edit box (usually 6 points is sufficient), click the OK button and then click the Refresh Window button .

To read a particular joint label, right click on the joint to bring up a form that displays the joint label.

29. Click the Set Select Mode button to exit Draw Mode and enter Select Mode.

30. Click the Select All button to select all objects.

31. Click the Edit menu > Replicate command to display the Replicate form. In that form:

• Select the Radial Tab.

• In the Rotate About Line area select the Parallel to Z option.

• In the Intersection of Line with XY Plane area verify that X is 0 and Y is 0.

• In the Increment Data area verify that the Number is 1 and the Angle is 90.

• Click the OK button to proceed with the replication.

32. Click the Get Previous Selection button .

33. Click the Edit menu > Replicate command to display the Replicate form. In that form:

• Verify the Linear Tab is selected.

• In the Increments area type 21 in the dy edit box.

• Verify that 0 is entered in the dx and dz edit boxes.

• Verify that 1 is entered in the Number edit box.

• Click the OK button to proceed with the replication.

34. Click in the window entitled X-Z Plane @ Y=0 to make sure it is active.

35. Click the Set YZ View button to change the view to a Y-Z elevation. Note that the title of the window changes to Y-Z Plane @ X=0.

36. Select all of the elements in the Y-Z plane @ X=0 by “windowing.”

37. Click the Edit menu > Replicate command to display the Replicate form. In that form:

• Verify the Linear Tab is selected.

• In the Increments area type 21 in the dx edit box.

• In the Increments area type 0 in the dy edit box.

• Verify that 0 is entered in the dz edit box.

• Verify that 1 is entered in the Number edit box.

• Click the OK button to proceed with the replication.

38. Click the Set XY View button to change the view to an X-Y plan. Note that the title of the window changes to X-Y Plane @ Z=0.

39. Select the four joints at this level by “windowing” or clicking on them individually.

40. Click the Assign menu > Joint > Restraints command to display the Joint Restraints form. In that form:

• Verify that the Translation 1, Translation 2 and Translation 3 boxes are checked.

• Verify that the Rotation About 1, Rotation About 2 and Rotation About 3 boxes are not checked.

• Click the OK button.

41. Click the Show Undeformed Shape button to reset the window display from joint restraints to undeformed geometry. Note that the window title changes.

42. Click the Move Up in List button to display the plan view at Z=25.

43. Click the Draw Rectangular Area Element button on the side toolbar or the Draw menu > Draw Rectangular Area command to display the Properties of Object form. Again, we can ignore the current property setting.

44. Click on joint 33 and then joint 15 to draw an area object over the entire plan.

45. Click the Set Select Mode button to exit Draw Mode and enter Select Mode.

46. Click on the area object to select it.

47. Click the Assign menu > Area > Automatic Area Mesh command to display the Assign Automatic Area Mesh form.

48. Fill in this form as shown in Figure C-4 and click the OK button.

49. Click the Show Undeformed Shape button to reset the window display.

50. Click the Move Up in List button to display the elevation view at Z=37.

51. Click the Draw Rectangular Area Element button or the Draw menu > Draw Rectangular Area command to display the Properties of Object form.

52. Click on joint 34 and then joint 16 to draw an area object over the entire plan.

53. Click the Set Select Mode button to exit Draw Mode and enter Select Mode.

54. Click on the area object to select it.

55. Click the Assign menu > Area > Automatic Area Mesh command to display the Assign Automatic Area Mesh form.

56. Fill in this form as shown in the adjacent figure and click the OK button.

57. Click the Show Undeformed Shape button to reset the window display.

58. Click the Set Display Options button (or the View menu > Set Display Options command) to display the Display Options for Active Window form. In that form:

• Uncheck the Labels box in the Joints area.

• Uncheck the Labels box in the Frames/Cables/Tendon area.

• Click the OK button.

59. Click the Define menu > Load Cases command to display the Define Loads form. In that form:

• Type LIVE in the Load Name edit box.

• Select LIVE from the Type drop-down box.

• Verify that 0 is in the Self Weight Multiplier edit box.

• Click the Add New Load button.

• Click the OK button.

60. Click the Define menu > Materials command to display the Define Materials form. In that form:

    • Highlight the CONC material and click the Modify/Show Material button to display the Material Property Data form. In that form:

      • Verify that the Mass per Unit Volume is 4.662E-03.

      • Verify that the Weight per Unit Volume is 0.15.

      • Click the OK buttons on the Material Property Data and Define Materials forms to exit all forms.

61. Click the drop-down box in the status bar to change the units to _.

62. Click the Define menu > Materials command to display the Define Materials form. In that form:

    • Highlight the STEEL material and click the Modify/Show Material button to display the Material Property Data form. In that form:

      • Verify that the Modulus of Elasticity is 29000.

      • Verify that Poisson’s ratio is 0.3.

      • Verify that the steel yield stress is 36.

      • Click the OK buttons on the Material Property Data and Define Materials forms to exit the forms.

63. Click the Define menu > Frame Sections command to display the Frame Properties form. In that form:

• Click the drop-down box that reads Import I/Wide Flange and select the Import Angle option.

• Click the Add New Property button to display the Section Property File form. Locate the Sections.pro file, which should be located in the same directory as the SAP2000 program files. Highlight Sections.pro and click the Open button.

• A form appears with a list of all angle sections in the database. In that form:

  • Scroll down and highlight the L4x4x1/2 by clicking on it.

  • Hold down the Shift key on the keyboard and click on the L4x4x7/16 angle. All of the L4x4 angles will now be selected (seven total).

  • Click the OK buttons on the two forms to return to the Frame Properties form.

• Click the drop-down box that reads Add I/Wide Flange and select the Add Auto Select option.

• Click the Add New Property button to display the Auto Selection Sections form. In that form:

  • Highlight all of the angles in the List of Sections list box by clicking on the top angle, pressing and holding down the shift key on the keyboard, and clicking on the bottom angle.

  • Click the Add button to add the angles to the Auto Selections list box.

  • Click the OK buttons on the Auto Selection Sections and Frame Properties forms to exit all forms.

64. Click the drop-down box in the status bar to change the units to .

65. Click the Define menu > Area Sections command to display the Area Sections form. In that form:

    • Click the Modify/Show Section button to display the Area Section Data form. In that form:

      • Verify the Material specified is CONC.

      • Verify that the Shell option is selected in the Area Type area.

      • In the Thickness area, type .6667 in both the Membrane and Bending edit boxes.

      • Verify that the Shell option is chosen in the Type area.

      • Click the OK buttons on the Area Section Data and Area Sections forms to exit all forms.

66. Click in the 3D View window to make sure it is active.

67. Click the Select All button on the side toolbar to select all objects.

68. Click the Assign menu > Frame/Cable/Tendon > Frame Sections command to display the Frame Properties form. In that form:

• Highlight the AUTO1 section.

• Click the OK button.

69. Click the Select All button to select all elements.

70. Click the Assign menu > Area Loads > Uniform (Shell) command to display the Area Uniform Loads form. In that form:

• Verify DEAD is selected in the Load Case Name drop-down box.

• In the Uniform Load area, type .05 (50 psf) in the Load edit box.

• In the Uniform Load area, verify that the Direction item is set to Gravity.

• Click the OK button.

71. Click the Select All button on the side toolbar to select all objects.

72. Click the Assign menu > Area Loads > Uniform (Shell) command to display the Area Uniform Loads form. In that form:

• Select LIVE in the Load Case Name drop-down box.

• In the Uniform Load area, type .1 (100 psf) in the Load edit box.

• Click the OK button.

73. Click the Show Undeformed Shape button to remove the display of the area loads.

74. Click in the window labeled X-Y Plane @ Z=37 to activate it.

75. Select all of the objects in the plan view by “windowing.”

76. Click the Assign menu > Joint > Constraints command to display the Assign/Define Constraints form. In that form:

• In the Choose Constraint Type for Add area, click the drop-down box that reads Body and select Diaphragm.

• Click the Add New Constraint button to display the Diaphragm Constraint form. In that form:

  • Type ROOF in the Constraint Name edit box.

  • Verify that the Z Axis option is selected in the Constraint Axis area.

  • Click the OK buttons on the Diaphragm Constraint and the Assign/Define Constraints forms to exit all forms.

77. Click the Show Undeformed Shape button to remove the display of the joint constraints and reset the window display.

78. Click the Move Down in List button to move to the X-Y Plane @ Z=25.

79. Select all of the objects in the plan view by “windowing.”

80. Click the Assign menu > Joint > Constraints command to display the Assign/Define Constraints form. In that form:

• In the Choose Constraint Type for Add area, click the drop-down box that reads Body and select Diaphragm.

• Click the Add New Constraint button to display the Diaphragm Constraint form. In that form:

  • Type SECOND in the Constraint Name edit box.

  • Verify that the Z Axis option is selected in the Constraint Axis area.

  • Click the OK buttons on the Diaphragm Constraint and the Assign/Define Constraints forms to exit all forms.

81. Click the Show Undeformed Shape button to remove the display of the joint constraints and reset the window display.

82. Click the Define menu > Analysis Cases command to display the Analysis Cases form. In that form:

• Click on MODAL in the Case Name list to highlight it.

• Click the Modify/Show Case button to display the Analysis Case Data form. In that form:

  • In the Number of Modes area, type 3 in the Maximum Number of Modes edit box.

  • Click the OK buttons on the Analysis Case Data and Analysis Cases forms to exit all forms.

83. Click the Options menu > Preferences > Steel Frame Design command to display the Steel Frame Design Preferences form. In that form:

• Select AISC-ASD89 from the Design Code drop-down box.

• Click the OK button.

84. Click the Run Analysis button to display the Set Analysis Cases to Run form. In that form:

• Verify that the DEAD, MODAL and LIVE analysis cases are all set to Run in the Action list.

• Click the Run Now button to run the analysis.

85. When the analysis is complete, check the messages in the SAP Analysis Monitor window (there should be no warnings or errors) and then click the OK button to close the Analysis window.

86. Click the Design menu > Steel Frame Design > Start Design/Check of Structure command to initiate the design. The design proceeds and when it is complete P-M interaction ratios are displayed.

87. Click the Design menu > Steel Frame Design > Display Design Info command to display the Display Steel Design Results form. In that form:

• Select the Design Input option. Verify that Design Sections is displayed in the drop-down box.

• Click the OK button. The sections chosen by the program are displayed.

Note: Zoom in using the Rubber Band Zoom button to view the chosen sections better.

88. Click the Show Undeformed Shape button to remove the display of frame sections and interaction colors.

89. If you have zoomed in for a better view of the chosen sections, then click the Restore Full View button .

90. Click the Design menu > Steel Frame Design > Verify Analysis vs Design Section command to display the number of members that changed sections between analysis and design. If this number is greater than 1, the analysis should be re-run with the sections chosen during design. Click NO to close the form.

91. Click the Run Analysis button to display the Set Analysis Cases to Run form. In that form:

• Verify that the DEAD, MODAL and LIVE analysis cases are all set to Run in the Action list.

• Click the Run Now button to run the analysis with the updated design sections.

92. When the analysis is complete check the messages in the SAP Analysis Monitor window (there should be no warnings or errors) and then click the OK button to close the Analysis window.

93. Click the Design menu > Steel Frame Design > Start Design/Check of Structure command to initiate the design.

94. Click the Design menu > Steel Frame Design > Verify Analysis vs Design Section command to display the number of members that changed sections between analysis and design. Steps 91 through 94 should be repeated until the adjacent form appears. Click OK to close the form.

95. Click the Design menu > Steel Frame Design > Verify All Members Passed command to display the number of members that do not pass the stress/capacity check. If members do not pass the stress/capacity check after all analysis and design sections match, the Auto Select Sections list will need to be altered to include larger sections. Click the NO button to close the form.

96. Click the Show Deformed Shape button (or the Display menu > Show Deformed Shape command) to display the Deformed Shape form. In that form:

    • Verify that MODAL is selected in the Case/Combo Name drop-down box.

    • Type 1 in the Mode Number edit box.

    • Click the OK button.

97. Click the Start Animation button , located in the status bar at the bottom of the SAP2000 window, to animate the mode shape.

98. Click the Right Arrow button , located in the status bar at the bottom of the screen, to view the second mode shape.

99. Click the Right Arrow button again to view the third mode shape.

100. Click the Stop Animation button , located in the status bar at the bottom of the SAP2000 window, to stop the mode shape animation.

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