Description

Major earthquakes of the last few decades have generated a great deal of interest in structural control systems, to mitigate seismic hazards to lifeline structures - in particular, bridges. Although, there has been substantial work in the recent past in the development of structural control systems, their effectiveness could not be compared by a systematic study. This is because they were applied to different types of structures and subjected to different types of loadings. In this study, seismic response of the Benchmark Highway Bridge, with passive and semi-active control devices is investigated. The problem is based on the 91/5 highway over-crossing at Southern California, USA. An investigation of the existing devices has been carried out to evaluate their effectiveness under different earthquakes. The present study explores the use of seismic isolators, namely, Friction Pendulum System (FPS), Variable Friction Pendulum System (VFPS) and Variable Frequency Pendulum Isolator (VFPI). The semi-active devices studied include Variable damper, Pseudo- Negative Stiffness (PNS) damper, and Piezoelectric Friction Damper (PFD).