Product(s):	SACS
Version(s):	23
Area:	Collapse

Problem

How does SACS calculate the maximum base shear for collapse analysis?

I see in the post view, it refers a value which does not match with the output listing result.

Solution

The base shear in Precede/Collapse View is computed based on the reactions in joints with fixity and the pilehead reactions using the following formulation.

Regarding the base shear reported in the listing file, the Collapse program reports the data into 2 break ups. One with Joint Reaction Report and the other one with Pile Head Reaction Report.

Let us walk through with an example as below.

Hence, in the collapse post view base shear of 20237.6 shall be shown.