I am running a response spectrum analysis using SAP and trying to determine base shear. However, when I have SAP output the "Base Reactions," and when I sum up all of the "Joint Reactions" SAP outputs for the base points of the structure, I can get very different numbers. For example:
Base Reaction: 34.0 kips
Joint Reactions*: 243.7 kips
* Sum of joint reactions at base points
Why is there this discrepancy? Which of these is the actual base shear? When I look in the SAP reference information, it seems to say they should be the same.
Thank you!
Base Reaction: 34.0 kips
Joint Reactions*: 243.7 kips
* Sum of joint reactions at base points
Why is there this discrepancy? Which of these is the actual base shear? When I look in the SAP reference information, it seems to say they should be the same.
Thank you!