典型重车作用下混凝土简支空心板桥冲击效应分析

Impact effect analysis of bridge with simply supported concrete hollow slab subjected to action of typical heavy vehicles

对于自重小、活恒载比较大的中小跨径混凝土空心板桥,过桥车辆自身动力特性对桥梁车载动力冲击的影响不容忽视.选取4种标准跨径的装配式混凝土空心板桥,考虑车速、桥面不平度等因素影响,基于自编的车桥耦合振动计算程序,通过数值分析方法开展重车车型对桥梁车载动力冲击效应影响的分析.结果表明,除桥面平整度状况和车速外,重车类型也是显著影响桥梁动力冲击效应的重要因素.基于数值分析结果,提出考虑重车车型和桥面状况两类因素的简支空心板桥动力冲击系数修正公式及参数的取值方法.

For the moderate-and small-span concrete hollow slab bridges with small dead load and large ratio of live load to dead load,the effect of vehicles dynamic characteristics on dynamic impact of this bridge type under moving trucks cannot be ignored.4 modular simply supported hollow concrete slab bridges with different standardized spans were selected and the influence factor such as vehicle speed and bridge deck unsmoothness was considered to analyze the influence of heavy vehicle type on impact effect on the bridges,by means of the self-made vehicle and bridge coupled vibration evaluation program and numerical analysis method.The result shows that,in addition to the bridge deck smoothness and vehicle speed,the vehicle type also be a key influence factor on impact effect on the bridge.Therefore,a modified impact factor formulas and parameter assignment method for simply-supported hollow slab bridge were presented on the basis of numeric computation result,where the influence of heavy vehicle type and bridge deck smoothness condition were taken into consideration.