Semi-active control for the seismic response of a tall building with skirt structure

This paper presents an analytical method for semi-active control of seismic responses of tall building, whose tower structure and skirt structure are connected to each other with ER/MR dampers. After constructing a rational mechanical model of ER/MR dampers, this paper develops a group of governing equations for semi-active control of structure-damper system. In accordance with the principles of instantaneous optimal active control, an 'Off-On Energy Dissipation' semi-active control algorithm is proposed, which is based upon optimal active control displacement. An earthquake-excited tall building with a 20-story tower structure and a 5-story skirt structure is used to validate the analytical method presented. The results of simulated computation imply that, as a kind of simple and effective intelligent control device, ER/MR dampers can significantly reduce the seismic' whiplash effect' of tall building with skirt structure as well as the seismic responses of whole structure.