Evaluation of restrainer effects on bridge response subjected to dynamic loads

Abstract

Abstract Highway bridges in seismic prone areas suffer a serious structural issue when subjected to a severe earthquake, which are the longitudinal hinge displacements. The hinge displacements might put the structure integrity in jeopardy when they exceed certain limits. High hinge displacements can cause fatal effects on the bridge structure including; bearing failure, unseating, and pounding of the adjacent superstructure decks. The aim of this study is to implement a numerical model which characterize the standard properties of a highway bridge and put it under a high intensity seismic excitation to examine its response. Then attempting to enhance the structure response using cable restrainers as means of displacement control. A parametric study is to be performed to investigate the effect of the restrainer material properties (Stiffness and Effective damping) on the efficiency of the cable restrainer in performing its intended purpose. The bridge was modelled and analysed using CSIBridge® finite element package. The obtained results have demonstrated a hazardous response of the bridge without the cable restrainer. However, a significant control capability was observed when applying the cable restrainer. Moreover, the parametric study has shown that, the performance of the cable restrainer is closely related to its stiffness as the stiffness value significantly contributes to displacement control and response stabilization. On the other hand, the effect of the effective damping value on the overall response was limited. Optimum cable restrainer have be chosen based on the parametric study and implemented to the model. The response was compared to the initial response without the restrainer. Eventually, the use of the cable restrainer had provided an impressive efficiency on displacement control and response stabilization.