重载铁路桥梁提速作用下动力性能试验研究

Experimental Study of the Dynamic Performance of the Railway Bridge of the Heavy-Duty Railway Under the Action of Acceleration

重载铁路提速可以显著提高铁路运量和经济效益,但是提速后可能会使桥梁冲击振动加剧,振幅加大,给桥梁结构带来不利影响,严重危及铁路行车安全。以朔黄铁路南运河特大桥为研究对象,通过有限元仿真分析结合现场动力性能试验,研究列车在提速作用下对桥梁结构动力性能的影响。结果表明:桥跨结构横向加速度值与列车轴重有关,横向振幅和横向加速度随速度增大而增大的趋势不显著,且实测结果表明该桥动力性能参数与理论分析规律吻合,验证了本文的仿真计算与荷载试验相结合的方法是可行的。

The acceleration of heavy-duty railways may obviously enhance the transportation capability and improve the economic effects of them.However,the acceleration of the railway may cause the impacting vibration of railway bridges to get sharper,and the vibration magnitude to get larger,both of which may exert an unfavorable effect on the bridge structure and seriously harm the safe operation of the railway.With the mega bridge across the South Canal of the Shuohuang Railway as the target of our research,and the finite element analysis method used for the simulation analyses combined with site dynamic performance tests,the effect of the train in the conditions of acceleration on the dynamic performance of the bridge structure is studied in the paper.The result of our research shows that the value of the lateral acceleration of the bridge structure is related to the axial weight of the train,while the tend of the lateral vibration magnitude and the lateral acceleration increasing with the acceleration is unobvious.Besides,the practically-measured results of the dynamic performance parameters of the bridge are found to be in agreement with the laws of theoretical analyses,which proves that the method for the simulation calculation combined with loading tests described in this paper is fully feasible.