Effect of soil-structure interaction on wind-induced responses of supertall buildings with large pile groups

Abstract

A simplified three-dimensional soil-structural interaction (SSI) model is established for large pile groups-supertall buildings (>300 m height) to simulate the dynamic response of the building to wind loading. The displacement and acceleration responses to wind loading at the top of the supertall building are calculated using the established model. The effects of SSI on the wind-induced mean displacement, root-mean-square (RMS) displacement and RMS acceleration are analyzed considering different values of soil shear wave velocity and material damping, and different total mass, first natural frequency and damping ratio of the superstructure as well as different terrain conditions. The results from the comprehensive parametric study are used to derive empirical equations of the mean displacement, RMS displacement and RMS acceleration SSI factors. The findings demonstrate that the mean displacement of the top of supertall building increases considering SSI. As the soil shear wave velocity decreases, the mean displacement SSI factor increases. It was also found that the mean displacement SSI factor increases with the increase in total mass and first natural frequency of the superstructure. In addition, the RMS displacement and acceleration SSI factors decrease with the increase of the soil shear wave velocity and material damping. Finally, the RMS displacement and acceleration SSI factors increase as the superstructure first damping ratio increases.