Set Time Period Targets

Form: Time Period Targets

For time period targets, specify a mode and a target period for that mode. Then, during design, ETABS automatically optimizes the structure to meet the target period using energy considerations. During the optimization process, members with large energy per unit volume are changed more than those with small energy per unit volume.

Assuming that appropriate steel frame, concrete frame, composite beam, composite column, or steel joist auto select list assignments have been made, the time period targets will be considered in steel frame design, concrete frame design, composite beam design, composite column design, or steel joist design.

Assign auto select sections to selected frames before running the analysis. Auto select section lists must be assigned to frame elements for the time period optimization to work. When ETABS increases or decreases a section size, it uses the available sizes in the auto select section list. If the appropriate sections are not included in the auto select lists, the displacement target may never be reached, no matter how many times the analysis and design are run.
Click the Design menu > Set Time Period Targets command to access the Time Period Targets form.
Click the Add button to specify the target data.
Use the Mode Number drop-down list and Target Period display/edit box to specify the time period target.

- Delete a Target. If necessary, highlight the target specification to be deleted. Click the Delete button.
- Ignore Specified Time Period Targets check box. Check this check box to exclude the time periods from a design iteration(s) without deleting them. Uncheck the check box to include time periods in design.