Hybrid seismic protection of cable‐stayed bridges

Abstract

SUMMARYThis paper proposes a hybrid control strategy combining passive and semi-active control systems for seismic protection of cable-stayed bridges. The e cacy of this control strategy is veriÿed by examining the ASCE ÿrst-generation benchmark problem for a seismically excited cable-stayed bridge, which employs a three-dimensional linearized evaluation bridge model as a testbed structure. Herein, conventional lead-rubber bearings are introduced as base isolation devices, and semi-active dampers (e.g., variable oriÿce damper, controllable uid damper, etc.) are considered as supplemental damping devices. For the semi-active dampers, a clipped-optimal control algorithm, shown to perform well in previous studies involving controllable dampers, is considered. Because the semi-active damper is a controllable energy-dissipation device that cannot add mechanical energy to the structural system, the proposed hybrid control strategy is fail-safe in that the bounded-input, bounded-output stability of the controlled structure is guaranteed. Numerical simulation results show that the performance of the proposed hybrid control strategy is quite e ective in protecting seismically excited cable-stayed bridges.

Semi-Active Control Systems in Bridge Engineering: A Review of the Current State of Practice

“…Additional papers were also published in Volumes 129(7) and 10(3-4) of the Journal of Structural Engineering (ASCE) and the Journal of Structural Control, respectively. The aforementioned studies along with additional ones published independently, included applications (with regard to semi-active control) of stiffness control devices 47,80 , friction control devices 47,81 , controllable fluid dampers [82][83][84][85][86] , negative stiffness devices 87 , and hybrid base isolation systems 88,89 .…”

Passive hybrid systems for earthquake protection of cable-stayed bridge

“…Iemura and Pradono [11] investigated the effectiveness of passive linear type dampers and semi-active variable dampers along with elastomeric bearings for the earthquake response control of a cable-stayed bridge. In addition, the performance of semi-active and active hybrid strategies for the earthquake protection of building and bridge structures, including cable-stayed bridges, are also investigated [12][13][14][15][16][17][18]. Although there are several investigations conducted into the application of passive hybrid systems for buildings and multi-span bridges, studies of flexible structures like cable-stayed bridges are meager.…”

Experimental investigations on seismic control of cable-stayed bridges using shape memory alloy self-centering dampers

“…Combining both the advantages of the passive and active devices, semiactive dampers were proposed to control the seismic behavior of the cable‐stayed bridges, including the resetting semiactive dampers and the magnetorheological fluid dampers . Hybrid control systems, which combine the passive and semiactive devices, are also investigated . Based on the semiactive dampers, Iemura and Pradono developed the pseudo negative stiffness dampers for controlling the seismic response of cable‐stayed bridges.…”