高速铁路桥上无缝线路力学计算模型对比

高速铁路桥梁、墩台及荷载均具有很强的空间力学特性，平面力学模型不能很好反映上述工况，有着较大的局限性。在吸收前人研究成果的基础上，建立了梁、轨纵向相互作用三维有限元空间力学计算模型，以秦沈客运专线32m多跨简支双线整孔箱形梁桥为例，对其进行了纵向力分析，并与传统平面力学模型进行了比较。对于伸缩附加力，平面模型与空间模型计算结果相差不大；对于挠曲附加力，平面模型与空间模型计算结果有较大的差别；当双线对称加载时，平面模型与空间模型制动附加力计算结果相差不大；在单线制动或双线对向制动时，平面模型的计算结果较多超过空间力学模型的计算结果，其计算结果是偏于保守的。对比分析表明空间力学模型更适宜于各种工况附加力的计算。

Mechanics computation model comparison of continuously welded rails on high-speed railway bridges

The girder, abutment and pier as well as the loads of high-speed railway bridges are of strong spatial mechanics characteristics, the plane mechanics calculation model cannot reflect these conditions effectively, and has its limitations. Based on the achievements of the predecessors, a three-dimensional finite element spatial mechanics model for calculating the additional longitudinal forces of continuously welded rails on high-speed railway bridges was established. Taking a 10-span 32 m simple supported double track box girder on Qin-Shen passenger special line as an example, the additional longitudinal forces were analyzed, and the calculation results of the new three-dimensional spatial model and traditional plane model were compared. The calculation results show that the flexiable additional longitudinal forces calculated by tow models are almost equal; for the winding force, there is distinct discrepancy between the two calculation results; when the double-track loaded with the symmetry braking force, the braking additional longitudinal forces calculated by the two models are almost equal; when one track braking or two track braking in opposite directions, the calculation result of the plane model is bigger than that of the spatial model, the braking additional longitudinal force calculated by the plane model is conservative, which indicate that the spatial model is more feasible and effective to calculate the additional forces than the plane model. 2 tabs, 5 figs, 22 refs.