I am performing a Modal Response Spectrum Analysis using a design spectra developed for the site. ASCE 7 Section 12.9 requires that the value of the base shear not be less than 85% of the base shear obtained using the procedures of Section 12.8. If I follow section 12.8, I end up calculating a static equivalent base shear based on MAPPED values of Ss and S1. Is this correct or should i use the values of Sds and Sd1 from the SITE SPECTRUM to calculate the static base shear to compare with the dynamic value?
Red Flag Submitted
Thank you for helping keep Eng-Tips Forums free from inappropriate posts. The Eng-Tips staff will check this out and take appropriate action.
Reply To This Thread
Posting in the Eng-Tips forums is a member-only feature.