Three-dimensional wind load effects and wind-induced dynamic responses of a tall building with X-shape

Three-dimensional wind load effects on a tall building with X-shape are investigated based on measured synchronous surface pressures in a wind tunnel. The mean and root-mean-square storey force coefficients in the three primary directions, i.e. along-wind, crosswind and torsional wind, of the building are presented. Wind-induced response analysis has been carried out in time domain by using the step-by-step numerical integration method, and the occupant comfort performance of the practical 42-storey building is checked against the Chinese tall building design code. In the dynamic analysis, the buildings are modelled by a lumped mass system having three degrees of freedom at each floor level, i.e. two orthogonal translations and one rotation about a vertical axis. A new resultant displacement projection method is proposed to calculate the gust response factors (GRFs) along two orthogonal coordinate directions for design purpose. Not only can the calculated GRFs ensure the synchronization among the maximum resultant displacement and the maximum component displacements along X- and Y-axes, but also are capable of taking crosswind effects into account. Copyright © 2009 John Wiley & Sons, Ltd