Per section 11.7 of ASCE 7-16, "Buildings and Other structures assigned Seismic Category A need only comply with section 1.4", except tanks in Risk category IV which shall satisfy the freeboard requirement in section 15.6.5.1. All Nonstructural components in seismic design category A are exempt from seismic design requirements.
Section 1.4 shows lateral forces to be calculated from the equation 1.4-1 and states "in each direction the static lateral forces at all levels shall be applied simultaneously"
So from my interpretation for buildings and other structures you would simply use Fx=0.01Wx for Seismic Category A, all other buildings and structures of Seismic Design Category B,C,D,E,F would need to follow other guidelines to calculate base shear as outlined in the code.
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Michelle Hudson EIT, A.M.ASCE
Design Engineer
Altoona IA
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