Optimum semi-active hybrid system for seismic control of the horizontally curved bridge with Magnetorheological damper

Abstract

Present paper investigates the application of Magnetorheological (MR) damper for a seismic control of the horizontally curved bridge isolated with different passive devices. The main aim of the study is to investigate the effectiveness of hybrid system for the seismic control of curved bridge with variation of important parameters. The selected bridge is a three span continuous concrete box girder supported on pier and rigid abutment. The bridge deck is model as a single spine beam, which is made with number of small straight two node beam elements and supporting pier model as linear lumped mass system. The MR dampers are located between the deck and abutments or piers in chord and radial direction. The bridge is excited with four different ground motions having different ground motion characteristics with all three-ground motion components (horizontal as well as vertical). The analysis results confirm use of MR damper with different isolator effective in controlling the response of the curved bridge and MR damper also effective in controlling the bearing displacement. The combination of MR and Lead rubber bearing (LRB) can provide an effective way for overall seismic control of curved bridge structure.