研究目的:高速铁路整体式桥梁的分跨布置、墩柱刚度等设计参数与梁轨相互作用密切相关,当参数取值不合理时,将出现桥上钢轨变形过大、失稳、断裂等问题。为确保桥上线路安全运行,得到设计参数的取值范围及相关关系,本文基于双折线、多折线非线性阻力模型来模拟梁轨纵向阻力,建立梁轨微段受力平衡方程来得到钢轨的应力与位移等参数。分别结合钢轨强度、梁轨相对位移、墩顶位移、轨缝宽度及钢轨稳定性等约束条件,确定出桥梁温度跨度和墩柱刚度的相互关系及取值范围。
研究结论:(1)温度跨度和墩柱刚度的取值主要受钢轨强度约束的影响,梁轨相对位移、墩顶位移、轨缝宽度和钢轨稳定性限值条件影响较小;(2)提出了温度跨度和墩柱刚度两个参数在规范限值条件下的相关关系计算公式;(3)本文算法及所得计算式可为整体式桥梁设计提供一定的参考。

Research purposes: The beam-rail interaction is closely related to the value of the design parameters of the high-speed railway internal bridge such as span layout and pier stiffness. When the values are not reasonable, the problems such as excessive deformation, instability and fracture of the rail on the bridge will occur. To ensure the safety of the lines on the bridge and obtain the value range and related relationship of the design parameters, this paper simulates the resistance of beam and rail based on the double-line and multi-segment broken lines, and establishes an equilibrium equation of the CWR to obtain the parameters like the additional stress and displacement of the rail. Combining rail strength, the relative displacement of beam and rail, displacement of pier top, rail gap width and rail stability, respectively, the relationship between the bridge temperature span and the piers' longitudinal stiffness and the value range are determined.
Research conclusions:(1) The temperature span and the piers' longitudinal stiffness are mainly affected by the rail strength constraint. The relative displacement of beam and rail, the displacement of the pier top, the rail gap width constraint and the stability of the rail have little influence. (2) The relevant calculation formulas for the two parameters of temperature span and piers' longitudinal stiffness under the limit of the code are put forward. (3) The algorithms and calculation formulas can provide a certain reference for the design of integral bridges.