Seismic reliability research of continuous girder bridge considering fault-tolerant semi-active control

Abstract

Continuous girder bridge is one of the most widely used bridge types at present, but its structural characteristics are not conducive to earthquake resistance. Therefore, it is of great practical significance to study the damping control of continuous girder bridges. Considering that the control device may fail due to external factors, this paper uses the magnetorheological damper as the damping device to carry out the research on the damping control of the large-span continuous girder bridge. The traditional damping control scheme is improved, and a semi-active control scheme considering fault-tolerance is proposed. That is, when some dampers fail, the fault-tolerant control algorithm provides compensation output to the control system. The seismic response and damping rate of bridges under different control schemes are compared and analyzed, and the seismic reliability of structures under different control schemes and different threshold conditions under random seismic excitation is obtained based on probability density evolution method and random ground motion model. It is found that the semi-active control scheme considering fault tolerance can still make the continuous girder bridge achieve the expected control effect when the control system has faults.