Hybrid protective systems for seismic-excited bridges

ABSTRACT

Recently, several hybrid protective systems have been explored for applications to seismic excited bridge structures. In particular, two types of aseismic hybrid protective systems have been shown to be quite effective rubber bearings and variable dampers (or actuators), and sliding systems. The control methods are based on the theory of variable structure system (VSS) or sliding mode control (SMC). Emphasis is placed on the direct output feedback controllers using only a few sensors. Sensivity studies are conducted to evaluate and compare the effectiveness of passive sliding isolators and hybrid protective systems for reducing the response of seismic-excited bridge structures. The advantages of each protective system are demonstrated by simulation results for a wide range of earthquake intensities.(AU)