Wind-induced stochastic response of controlled tall buildings by complex-mode analysis

Abstract

This paper deals with the along-wind dynamic response of tall buildings passively controlled by Cross-Tensioned Spring Damper (CTSD) mechanisms. In order to estimate the dynamic response more accurately and efficiently, the building and its CTSD controllers were considered as a coupled non-classical damping system and a new stochastic response analysis method, complex-modal state-space method, was proposed based on the combination of complex modes of the structural system rather than on the real-modal decomposition as usual. As numerical examples, the displacement response of a 2-degree-of-freedom system to white-noise input is first considered and the validity and accuracy of the proposed method are demonstrated through comparison with the exact results. The wind-induced dynamic responses of a tall building controlled by two CTSD mechanisms are then analyzed. The calculation results showed that the proposed method is much more appropriate and accurate than the conventional real-modal decomposition method in the analysis of dynamic responses of passively controlled tall buildings.