客运专线斜拉桥梁轨相互作用设计参数

采用非线性弹簧模拟桥梁和轨道的相互作用,根据相关文献的试验结果对模拟方法进行验证。以沪昆客运专线上某槽型截面独塔斜拉桥为算例,采用大型通用有限元软件ANSYS建立了塔-索-轨-梁-墩统一的空间有限元模型,对斜拉桥钢轨纵向力的传递规律进行了分析,研究了纵向阻力模型、斜拉桥结构体系、温度荷载与风荷载等设计参数对钢轨纵向力的影响。分析结果表明:钢轨纵向阻力可按理想弹塑性模型进行简化;与漂浮体系相比,塔梁固结可减小约30%的钢轨纵向力;在计算钢轨伸缩力时可按照梁体升温15℃和拉索升温40℃加载;在风速较大的地区,风力引起的斜拉桥上钢轨纵向力可超过60kN。

Design parameters of track-bridge interaction on passenger dedicated line cable-stayed bridge

Track-bridge interaction was simulated by using nonlinear spring,and the simulation method was proved based on the experimental results of related documents.Taking a U-shape section and single-tower cable-stayed bridge on Shanghai-Kunming Passenger Dedicated Line as an example,the spatial finite element model of tower-cable-rail-beam-pier was established by using large general-purpose finite element software ANSYS.The transfer law of rail longitudinal force on cable-stayed bridge was analyzed,and the impacts of design parameters on rail longitudinal force were studied,the design parameters included longitudinal resistance model,cable-stayed bridge structure system,temperature load,wind load and so on.Analysis result shows that rail longitudinal resistance can be simplified in accordance with ideal elastic-plastic model.Compared with floating system,rail longitudinal force reduces by about 30% through tower and beam consolidation.When calculating rail expansion force,load can be applied according to beam increasing-temperature 15 ℃ and cable increasing-temperature 40 ℃.In windy areas,rail longitudinal force on cable-stayed bridge caused by wind can be larger than 60 kN.