Effect of System Uncertainty on Control of Seismic‐Excited Buildings

Abstract

A sensitivity study is conducted to investigate the effect of uncertainties in system identification on the performance of the active control system for seismic‐excited buildings. Four control algorithms feasible for applications to seismic‐excited buildings have been examined, including the linear quadratic optimal control algorithm and three instantaneous optimal control algorithms. A simple simulation approach is used for the sensitivity analysis. Both the active tendon control system and the active mass damper system have been considered. Numerical examples are worked out to illustrate the effect of uncertainties in identifying stiffnesses and dampings on the active control system. The effect of parametric uncertainties on the performance of active control systems for seismic‐excited buildings depends on the particular control algorithm used. It is demonstrated that, while dampings of structures are difficult to identify, the accuracy of damping estimation has a negligible effect on the performance of the control system. For some control algorithms, however, care should be taken to estimate the structural stiffness.