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Re: plan irregularity type 4 - 97 UBC

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Mark,
 
The example in the Seismic Design Manual you reference is incorrect.  1633.2.9 and 1633.2.9.6 specifically states the transfer force is to be added to Fpx, not Omega level forces.  Additionally 1633.2.9.6 limits the applicability of the allowable stress increases for the connection of the diaphragm to the vertical elements, not the diaphragm.  1630.8 is for overturning forces due to discontinuous systems, not the shear forces.
 
Ben is correct in that Omega level forces are not applied to Fpx or Fpx + transfer.
4a. Apply omega to Fpx?[Yousefi, Ben]  No [Mark] I must point out that the example in Volume II (page 75) applies omega to Fpx for this condition.
4b. Apply omega to load from wall above?[Yousefi, Ben]  Question is not clear 
 
Expanded 4b.: When adding the shear wall force (wall above) to the diaphragm force Fpx, should omega be applied to the additive shear wall force? I don't beleive so because the shear wall force is a result of the base shear equation which will have rho factored in. You would really be piling up the load by also applying omega.