Seismic Loads tab

Used to apply previously defined UBC loads on the structure.

Note: If a seismic load definition has not yet been added to the model, a warning message is displayed in the dialog and the controls are inactive. Refer to the dialog to learn more about defining a seismic load.

Setting

Description

Direction group

Specify the global direction in which the seismic load is to be generated by selecting the X Direction, Y Direction, or Z Direction radio button.

Setting	Description
Factor	Specify a multiplying factor, if applicable. The default factor is 1.0.

Multiplying factor for Accidental Torsion Moment

Set this option to include the accidental torsion load per the UBC, IBC, 1893, etc. code. Type the Factor in the associated field (may be a negative value).

Multiplying factor for Natural Torsion Moment

Set this option to include the torsion arising due to static eccentricity which is the difference between center of mass and center of rigidity of a rigid floor diaphragm. Type the Factor in the associated field (must be greater than or equal to zero).