Hybrid control of irregular steel highrise building structures under seismic excitations

Control of irregular highrise building structures under various seismic excitations is investigated using a hybrid control system consisting of a passive supplementary damping system and a semi-active tuned liquid column damper (TLCD) system. Equations of motion for the combined building and the TLCD system are derived for multistorey building structures with rigid floors and plan and elevation irregularities. Major steps involved in optimal control of three-dimensional irregular buildings equipped with a hybrid damper-TLCD system are delineated. A wavelet-based optimal control algorithm is applied to find the optimum control forces. Simulation results for control of two multistorey momentresisting space steel structures with vertical and plan irregularities show clearly that the hybrid damper-TLCD control system significantly reduces responses of irregular buildings subjected to various earthquake ground motions as well as increases reliability and maximum operability during power failure.