Factor for Seismic Design

Enter factors for special seismic loads and vertical seismic forces, which will be applied to specific members selected by the user in design.

From the Main Menu select Design > General Design Parameter > Factor for Seismic Design.

From the Menu tab of the Tree Menu select Design > General Design Parameter > Factor for Seismic Design.

The following dialog box is used to enter the data:

Special Seismic Loads

Vertical Load Factor: Enter a factor, which will be used to consider vertical seismic forces in special seismic loads.

Sds: Enter the short period spectrum acceleration calculated in the load entry part.  

System Over-Strength Factor

Load Case: Select seismic loads in each direction for which System Over-Strength Factors will be applied.  

Over-Strength Factor: Specify Over-Strength Factors for seismic force resisting systems in each direction.   

Add: Select a Load Case for seismic load and enter an Over-Strength Factor.

Modify: Modify a selected Load Case for seismic load and the Over-Strength Factor.

Delete: Delete the selected data, which has been already entered. Define the type of structural frame.

Vertical Seismic Forces

Vertical Force Factor: The factor applies to the Dead Load.  The factored Dead Load is acting upward, which replaces all the Dead Load terms in load combinations for design for selected elements.