浮置板板下胶垫的温变特性及其对轮轨系统的影响

以我国地铁常用浮置板板下胶垫为研究对象,测取-40~30℃的温度环境中板下胶垫的静刚度。建立车辆-浮置板轨道垂向耦合动力学模型,分析板下胶垫的温度敏感性以及不同温度环境下板下胶垫温变刚度对轮轨系统动力响应特征。研究结果表明:板下胶垫静刚度在工作荷载范围内为常量,不具有幅变非线性特征。板下胶垫的线性静刚度随着温度的降低而急剧升高,增幅高达224%以上。板下胶垫的温变刚度主要影响橡胶隔振垫浮置板轨道的浮置板位移,浮置板垂向最大位移变化率可达到204%。其次,板下胶垫的温变刚度对钢轨的垂向位移也会产生一定的影响,钢轨垂向最大位移变化率为31%。板下胶垫的温变刚度对轮轨之间作用力产生的影响较小。

Temperature Variant Characteristics of Rubber Pad under Floating Slab and Their Impact on Vehicle-track Coupled System

With reference to the commonly used rubber pad under the floating slab,the static stiffness of the rubber pad is measured in the temperature range between-40 ℃ and 30 ℃,and the vehicle floating slab track coupled dynamic model is established to analyze the temperature-sensitivity of the rubber pad and the influence of temperature-dependent stiffness of the rubber pad. The research results show the static stiffness of the rubber pad in the working load range is a constant without amplitude dependent nonlinear characteristics. The static stiffness of the rubber pad shows a sharp increase when the temperature decreases and the increased amplitude reaches 224 percent,which reveals that the rubber pad is sensitive to low temperature. The change of rubber pad stiffness mainly affects the displacement of the floating slab,and the maximum change rate of displacement may reach 204 percent.Furthermore,the change of rubber pad stiffness has certain impact on the displacement of the rail and the maximum change rate of rail displacement may reach 31 percent. Therefore,the influence caused by the change of the rubber pad stiffness on the wheel-rail forces is small.