专用铁路桥梁服役性能及汽车撞击动力响应  

Service Performance of Special Railway Bridge and Dynamic Response under Vehicle Impact

作　　者：彭泽 唐怀平[1] PENG Ze;TANG Huai-ping(School of Mechanics and Engineering,Southwest Jiaotong University,Chengdu Sichuan 610031,China)

机构地区：[1]西南交通大学力学与工程学院,四川成都610031

出　　处：《机械研究与应用》2021年第5期27-32,共6页Mechanical Research & Application

基　　金：国家自然科学基金项目:基于冲击动力学的船桥碰撞效应、损伤识别与防护关键技术研究(编号:5177080908)。

摘　　要：以某厂矿专用铁路线桥梁为研究背景,基于静载试验考核桥梁结构的强度和刚度,评定其在设计活载作用下的承载能力;基于动载试验测试了桥梁结构的动力特性参数,评定其服役性能是否符合安全运营性要求;对废渣罐车扩容增重后桥跨主梁在主力、主力+附加力组合作用下,破坏阶段构件承载力安全系数和结构抗裂性进行详细检算;考虑车辆撞击对桥梁的危害,通过有限元分析软件MIDAS-Civil建模计算,分析了不同碰撞力持时作用下主梁跨中位置的动力响应。研究结果表明:桥梁承载能力满足设计荷载的使用要求,动力性能较好,运营性能满足现行规范要求,轴重增加后结构强度和抗裂性不满足要求,汽车撞击对桥梁动力响应有一定影响。In this article,a special railway line bridge in a mining area is taken as the research background. Based on the static load test,the strength and stiffness of the bridge structure are evaluated,and its bearing capacity under the design live load is evaluated. Based on the dynamic load test,the dynamic characteristic parameters of the bridge structure are tested to evaluate whether its service performance meets the requirements of safe operation. The safety factor of component bearing capacity and structural crack resistance in the failure stage under the combined action of main force,main force + additional force of the main girder of bridge span after the expansion and weight increase of the waste slag tank car are calculated in detail. Considering the harm of vehicle impact on the bridge,the dynamic response of the mid-span position of the main girder under different durations of impact forces is analyzed by the finite element analysis software MIDAS-Civil. The results show that the bearing capacity of the bridge meets the requirements of the design load;the dynamic performance of the bridge is good,and the operation safety meets the requirements of the current specifications. When the axle load of bridge increases,the structural strength and the crack resistance could not meet the requirements;and the vehicle impact has a certain influence on the dynamic response of the bridge.

关 键 词：铁路桥梁 荷载试验 桥梁检算 车桥碰撞 动力响应 

分 类 号：U442.5[建筑科学—桥梁与隧道工程]