Response Spectrum Analysis of Peak Floor Accelerations of Buildings under Earthquakes

The design of acceleration-sensitive nonstructural elements is closely related to the peak floor acceleration (PFA) responses. We propose an improved method for estimating PFAs in buildings during earthquakes. This introduces a complementary mode accounting for the ground accelerations properly. It is equally practical as conventional response spectral analysis but provides accurate predictions of PFA at the base. We first derive the representative PFA distribution for the complementary mode upon linear dynamic analyses and then generalize the method to nonlinear cases. An error analysis concludes that the proposed method is promising for both linear elastic and moderately inelastic cases.