Cubic control for phase I smart base-isolated benchmark building with emphasis on nonstructural performance

Most control techniques in the structural engineering literature are aimed at improving performance of the primary structural system, but may have limited or even adverse effect on nonstructural components during strong seismic events. In this paper, we emphasize nonstructural performance using an active controller with a cubic nonlinearity. The controller is optimized based on the frequency response functions of a SDOF nonlinear oscillator. An eight-storey base-isolated benchmark building recently proposed by the ASCE structural control committee is studied as a demonstration by considering both structural and nonstructural performance indices. We compare the performance of the proposed cubic controller with that of a LQG-based semiactive control system and a passive energy dissipation system. It is shown from the simulation results that in most benchmark test cases, the cubic control system produces better nonstructural performance while maintaining good response characteristics of the primary structural system. Further research directions for this cubic control system are also pointed out. Copyright # 2005 John Wiley & Sons, Ltd.