Investigation on using MR dampers to mitigate seismic responses for self-anchored suspension bridges

Based on aseismic theory of bridge structure and mechanical model of magnetorheological(MR) damper, the seismic response reduction system composed of bridge structure and MR damper is established. Program SRALB is compiled and can be used for seismic response analysis and seismic response reduction analysis of long-span bridges. Furthermore seismic response reduction research of Pingsheng Bridge, a single-tower self-anchored suspension bridge in Foshan Guangdong province, is investigated with program SRALB. The effect of seismic response reduction by varied electronic current, number of MR dampers is discussed. The research shows that MR damper can effectively reduce longitudinal seismic responses of self-anchored suspension bridge. With the increasing of electronic current and number of MR dampers fixed in the longitudinal direction between tower and girder, longitudinal displacements of tower and girder decrease, and inner force responses of the structure can effectively be controlled.