Evaluation of critical separation distance to avoid seismic pounding between buildings: A spectral approach

Abstract

AbstractDetermining a minimum separation distance required to avoid seismic pounding between adjacent buildings is a capacity‐demand design issue. This study developed a spectral approach to evaluate the expected minimum separation demand (referred to as the critical separation distance, [CSD]) to prevent pounding between buildings during strong earthquake motions. Presented firstly in this paper is an analytical procedure for evaluating the relative displacement process at the potential pounding location between two adjacent buildings during earthquake motions. The procedure is based on random vibration theory and modal analysis with application of the well‐known CQC rule. Subsequently, an approximate nonlinear closed‐form solution for evaluating CSD is derived, by means of a simplified spectral‐based procedure with introducing the concept of equivalent linearization of nonlinear hysteretic behavior and the effective correlation coefficients of the generalized coordinates of equivalent linearized systems to consider inelastic vibration phase between buildings. Finally, the CSDs between two buildings having different heights and the same height for various combinations of buildings with different fundamental periods are separately examined as verification examples of the proposed approach. The accuracy of solution is demonstrated by comparing computed results with corresponding numerical results from nonlinear response history analyses (RHAs). The results show that the proposed approach provides a reliable solution in predicting the separation demand of buildings during earthquake motions.