Effective Seismic Weight? 1

[SteelPE]

Believe it or not I am having another disagreement with someone in my office on how to calculate the effective seismic weight of a building. This disagreement involves what to do with the walls that run parallel to the assumed direction of the seismic load. I have always included the weight of these walls when calculating the base shear on the structure. The only time I don’t include them in the seismic weight of the building is when the wall is a structural element (for example CMU).

The reference project is a steel framed building with a brick façade. I included the weight of the entire perimeter (because I don’t want to drive lateral loads through a veneer) while he is saying I don’t need to include the walls that run parallel to the seismic load. Applicable code is IBC09.

How do others handle this situation?

 

[saad73joss]

Hello
The mass should be taken entirely for seismic load
As for wind versus seismic it depends the type of structure and since we have important load located in a significant height the seismic could be governing....

 

[PicoStruc]

saad73joss -> True.

I saw a increase in seismic force only due to the green roofing that is now quite popular !

I would add that sometime, wind govern on a certain height and the seismic can govern on another !