重载铁路非等跨简支梁桥上无缝线路纵向力研究

为研究重载铁路非等跨简支梁桥上无缝线路纵向力的分布规律,建立6-32 m+40 m+6-32 m(30 t轴重)重载铁路简支T梁与轨道相互作用有限元模型,与13-32 m简支梁桥相对比,研究温度、竖向活载、列车制动及地震作用下系统的受力和变形特征,探讨非等跨简支梁(40 m简支梁)对系统的影响规律。研究表明,各类荷载作用下,钢轨应力峰值多集中在各简支梁相接处及跨中位置;地震作用下,钢轨和墩底承受着极大的纵向力;非等跨简支梁桥对伸缩力和挠曲力影响较大,将使钢轨伸缩拉应力增大70%、钢轨挠曲应力增大50%、部分桥墩墩顶挠曲力增大50%;非等跨简支梁桥对制动力和地震力影响较小。

Longitudinal Force of CWR on Unequal Span and Simply-supported Beam Bridges on Heavy Haul Railway

In order to study the longitudinal force of CWR(continuously welded rail) on unequal span and simply-supported beam bridges,a finite element model is established for the interaction between 6-32 m+40 m+6-32 m(30 t axle) heavy haul railway simply-supported T beam and the track. The stress and deformation characteristics of system due to temperature-increase,vertical live load,brake and earthquake are studied in comparison with the 13-32 m simply supported beam. The influences of the unequal span and simply supported beam(40 m simply supported beam) on the system are analyzed. The studies show that the rail peak force is concentrated where simply supported beams are connected and in mid span; under the action of earthquake,the rail and the pier are subject to huge longitudinal force; the impact of the unequal span and simply supported beam bridge on contractility and bending force is larger,which increases the rail tensile stress by 70%,rail flexural stress by 50%,and partial pier top flexural stress by 50%; the influence of unequal span and simply supported beam bridge on the braking force and earthquake force is small.