Time-history response analysis on buffeting vibrations of tall buildings

Abstract

This paper deals with the resistance of buildings to strong winds in the light of the ultimate strength concept. The structural behavior is limited to the buffeting vibration along the wind direction. The applied method is a direct numerical analysis based on the time history of drag forces which has been measured on scale models in a wind tunnel.First, the elastic response of structure is analysed under a stationary turbulent flow. The maximum deformation response and the energy input to the structure exerted by wind forces are obtained. Also, the number of cycles of buffeting vibration is calculated in terms of the equivalent number of cycles effective in evaluating fatigue strength of structural components.Next, the inelastic response analysis is made, and it is demonstrated that the inelastic energy absorption capacity of structure is effective to increase the structural resistance against wind loading, as is recognized under the seismic loading.Finally, the results of analysis is generalized to apply to the case of typhoons where the wind velocity changes with a definite pattern.