Semiactive Control System based on MR Damper for Suppressing Vibration of Stay Cable under Wind Load

This paper investigates the performance of the semiactive control system based on magnetorheological fluid (MR) dampers for suppressing excessive vibration of stay cable installed in cable-stayed bridges under wind load. The cable model is extracted from a 156.3 m long stay cable with high tension. The external wind load is generated from the widely used wind load spectrum such as the Kaimal spectrum. Several semiactive control algorithms such as the Lyapunov stability theory-based control, the maximum energy dissipation and the clipped-optimal control are considered to find the appropriate control strategy for the cable-damper system employing MR dampers. Numerical simulations are carried out to demonstrate the effectiveness of the semiactive control systems based on MR dampers and their control performances are compared with those of passively operated control systems.