地震作用下桥梁防碰撞及防落梁措施研究综述

A review of measures for preventing bridge from pounding and unseating damages

桥梁作为生命线工程的重要组成部分,一旦在地震中发生破坏,会造成巨大的经济损失和社会损失。地面上相邻的桥跨结构由于其动力特性存在差异及地震动输入的空间变化特性,地震发生时会引起相邻桥跨间的非同向振动,当桥跨间预留的间隙不能满足彼此的相对位移时就会发生相互碰撞,间隙过大时很容易引起落梁。针对相邻桥跨间的碰撞和落梁问题,对历次大地震中与碰撞和落梁相关的震害进行了回顾,介绍了纵桥向各种防碰撞与防落梁措施的研究现状,主要包括限位器、阻尼限位装置、模数式伸缩缝、减震装置以及组合限位装置五个方面。同时通过对研究现状的分析对以上各种防碰撞与防落梁措施的优点和缺点分别进行总结,进而对有待进一步研究的问题进行了展望。

Huge economic loss and social loss would be occurred when the bridge was damaged in the earthquake which was regarded as an important part of lifeline engineering. Due to the dynamic characteristics and the spatial variation characteristics of the ground motion, an out-of-phase vibration between the adjacent bridges was caused during the earthquake. During seismic events, poundings between the adjacent bridge components can occur when the relative closing displacement is larger than the expansion gap size. On the other hand, unseating failure occurs when the expansion gap size is too large. Based on the pounding and unseating phenomenon between the adjacent bridge segments, the damages of the previous earthquakes were reviewed. The state of pounding and unseating miti- gation measures including restrainers, damping devices, modular expansion joints, shock absorbing device and hy- brid devices were presented. The merits and limitations of these measures were summarized systematically, and some topics which were worth studying further were proposed.