Thanks WillisV! I suppose that's a reasonable concern. Any idea where the number 85% comes from?
Setting an absolute minimum like 85% for all structures doesn't really correlate to the adverse effects of modeling. It affects structures with long periods far more than it affects structures with...
Can anyone explain why, in a Modal Response Spectrum Analysis, the code requires that the modal base shear is scaled up to 85% of the calculated base shear (ASCE 7-05 section 12.9.4)?
Thanks all!