Form: Select Sections
Because design is an iterative process, after a concrete frame design has been run, the design section property assigned to one or more frame object may need to be changed. SAP2000 allows multiple design iteration to be run without rerunning the analysis, which can save computing time.
Change a design section and redesign the structure without rerunning the analysis as follows:
Select the Analyze menu > Run Analysis command to analyze the model.
Select the Design menu > Concrete Frame Design > Start Design / Check of Structure command to complete the initial design. As necessary, use the Design menu > Concrete Frame Design > Interactive Concrete Frame Design command to evaluate the results.
Select the frame object(s) for which the section is to be changed.
Select the Design menu > Concrete Frame Design > Change Design Section command to access the Select Sections form. Choose the new section from the display list.
TIP: If nothing is shown in the list, additional concrete frame section definitions should be added to the model using the Define menu > Frame Sections command.
Repeat Steps 2 through 4 as necessary.
The Change Design Section command only changes the design section for the selected frame object(s). The forces used in the design are not based on this new section size but are instead based on whatever section was used in the last analysis.
Recall, however, that the design section property is used for the next analysis section property. Thus, changing the design section property also changes the next analysis section property.