INELASTIC RESPONSES OF WIND-EXCITED TALL BUILDINGS WITH BILINEAR HYSTERETIC RESTORING FORCE CHARACTERISTICS

This study deals with uncoupled inelastic crosswind and alongwind responses of tall buildings under ultimate wind excitations. The building dynamics is represented in terms of fundamental mode with a bilinear hysteretic restoring force character. The statistical linearization technique is applied to determine the random inelastic zero-mean crosswind response and non-zero mean alongwind response. The effectiveness of statistical linearization is illustrated though the comparison with the response derived from response time history simulations. A comprehensive parametric study is performed to examine the distinct inelastic response characteristics under alongwind and crosswind excitations. The results demonstrate that the inelastic crosswind response is lower than that of corresponding linear system attributed to the increase in damping resulted from the hysteretic restoring force. On the other hand, the increase in the mean alongwind response due to response drift after yielding can lead to total inelastic alongwind response noticeably higher than that of the corresponding linear system.