强震作用下大跨斜拉桥伸缩缝处碰撞效应的影响研究

大跨斜拉桥一般采用飘浮体系或者弹性约束体系，其在强震作用下梁端会发生很大位移，梁端的过大位移可能会导致主梁与相邻跨引桥的碰撞，使整个结构丧失整体性。本文针对强震作用下大跨斜拉桥伸缩缝处的碰撞现象，以一座典型大跨斜拉桥为例，建立了考虑引桥墩柱、塔柱弹塑性的空间非线性碰撞模型，采用非线性时程法研究了大跨斜拉桥伸缩缝处相邻跨梁体碰撞对桥梁结构地震反应的影响。研究结果表明：由于大跨桥梁结构主、引桥结构体系不同，在强震作用下主引桥相邻梁体易发生碰撞，碰撞不仅会产生很大的撞击力，而且使引桥地震力需求、引桥梁端位移、主引桥相对位移及引桥梁体搭接长度需求有较大增长，极易造成引桥的落梁或者破坏；而碰撞效应对主桥的地震需求影响较

Effect of pounding at expansion joints on seismic response of long-span cable-stayed bridge under strong earthquake

Based on the pounding phenomenon at expansion joints of a typical long-span cable-stayed bridge under strong earthquake,the complex nonlinear model considering the elasto-plastic behaviors of piers and pylon as well as the relative pound responses between main span and approach span was developed.With the time history analysis for determining the nonlinear seismic responses,the pounding effects of adjacent girders at expansion joints on seismic responses of the bridge were studied.The results indicate that ...