The upper value of 'Cs' computed in accordance with eq. 12.8-2 need not exceed eq. 12.8-3 or 12.8-4, whichever applies. In Frame, under 'Loads and Applied Forces', this check doesn't appear to be included. What am I missing?
Thank you for your prompt response. Exception 2 of 11.4.8 applies, which limits the upper value of Cs to 1.5 * eq 12.8-3, which I overlooked. If one is in possession of site ground motion hazard analysis parameters, how do I use the program such that the exceptions of 11.4.8 are not applied?
We don't have a convenient way to force the program to use a specific Sds value (or Sd1 value) for site-specific data. I usually suggest user defined story force because then you are in complete control. manipulating the load case input (T, Ss, S1) does not always result in the specific desired output.
What might be useful is a kind of generic seismic load where the user would provide those values directly, but the program would still do the vertical distribution of the force and the accidental eccentricity work automatically. Let us know what might work well for you.