Steel Frame Design Procedure

Following is a typical steel frame design process that might occur for a new building. Note that the sequence of steps taken in any particular design may vary but the basic process will probably be essentially the same.

Note: This procedure uses the menu commands. The same functions can be accessed using the Model Explorer.

  1. Use the Design menu > Steel Frame Design > View/Revise Preferences command to choose the steel frame design code. In addition, this command allows review of and changes to other steel frame design preferences. ETABS provides default values for all  preferences so this command can be used to review the values and to make changes when necessary.

  2. Create the building model.

  3. Run the building analysis using the Analyze menu > Run Analysis command.

  4. The following three commands can be used to tailor the design process to meet specific requirements, although their use  is not mandatory to complete a design.

  1. Designate lateral displacement targets for various load cases using the Design menu > Steel Frame Design > Set Lateral Displacement Targets command.

  2. Click the Design menu > Steel Frame Design > Start Design/Check command to run the steel frame design.

  3. Review the steel frame design results using any of the following methods:

  1. Use the Design menu > Steel Frame Design > Verify all Members Passed command to verify that no members are overstressed or otherwise unacceptable.

  2. Use the Design menu > Steel Frame Design > Change Design Section command to change the design section properties for selected frame elements.

  3. Click the Design menu > Steel Frame Design > Start Design/Check command to rerun the steel frame design with the new section properties. Review the results using the procedures described above.

  4. Rerun the building analysis using the Analyze menu > Run Analysis command. Note that the section properties used for the analysis are the last specified design section properties.

  5. Compare the lateral displacements with the lateral displacement targets.

  6. Click the Design menu > Steel Frame Design > Start Design/Check command to rerun the steel frame design with the new analysis results and new section properties. Review the results using the procedures described above.

  7. Repeat the process in steps 9 through 13 as many times as necessary to complete the design.

  8. Select all frame elements and click the Design menu > Steel Frame Design > Make Auto Select Section Null command. This removes any auto select section assignments from the selected frame elements (if they have the Steel Frame design procedure).

  9. Rerun the building analysis using the Analyze menu > Run Analysis command. Note that the section properties used for the analysis are the last specified design section properties.

  10. Verify that the lateral displacements are within acceptable limits.

  11. Click the Design menu > Steel Frame Design > Start Design/Check command to rerun the steel frame design with the new section properties. Review the results using the procedures described above.

  12. Click the Design menu > Steel Frame Design > Verify Analysis vs Design Section command to verify that all of the final design sections are the same as the last used analysis sections.

  13. Use the File menu > Create Report command to print selected steel frame design results.

IMPORTANT NOTE: Design is an iterative process. The sections used to run the original analysis typically are not the same sections as those used at the end of the design process. The Design menu > Steel Frame Design > Verify Analysis vs Design Section command is useful for making sure that the design sections are the same as the analysis sections. Always be sure to run a building analysis using the final frame section sizes and then run a design check based on the forces obtained from that analysis to ensure that the analysis results reflect the final design.