Semi-active magnetorheological dampers for reducing response of high-speed railway bridges

Abstract

To reduce the resonant response of high-speed railway bridges, semi-active magnetorheological dampers are proposed in this study. The elements are connected to the structure in a double beam configuration. An H∞ control algorithm to drive magnetorheological damping forces of MR dampers is derived. Feasible solutions for an uncertain time-delay model are obtained by using standard linear matrix inequality techniques. Weight functions as a loop shaping procedure are also introduced in the feedback controllers to improve the tracking ability of magnetorheological damping forces. To this end, the effectiveness of magnetorheological dampers controlled by the proposed scheme, along with the effects of the uncertain and the time-delay parameters on the models, are evaluated and compared with the performance of fluid viscous dampers in similar applications reported in previous research through numerical simulations.