列车荷载作用下板式轨道与饱和地基动力分析

Analysis of Dynamics of Slab Track and Saturated Foundation Under Train Load

研究目的:近年来随着我国大量高速铁路的建成及投入运营,列车高速运行对周边环境振动的影响日益显著。且在沿海地区,高速铁路干线修建在饱和软土地基上,饱和软土地基具有剪切波速低、含水量高等特性,高速列车会在饱和软土地基上引起较大的振动响应。因此,本文采用板式轨道-饱和地基耦合振动模型研究了高速列车荷载作用下轨道和饱和土体的振动响应问题,为有效解决高速列车引起的环境振动问题、优化高速铁路路基设计提供理论指导。研究结论:数值分析结果表明,采用多孔饱和介质模拟饱和土地基能够更准确地分析高速列车引起的振动响应,增大轨道刚度可有效控制钢轨位移响应,且在路基设计过程中合理控制基床厚度可减小土体中液相介质的存在对土体动力响应的影响。

Research purposes： With the more and more high -speed railways being putting into service, the VlDratlon influence of high - speed train on the surrounding environment is increasing gradually. In the coastal area, many high - speed railways are built on saturated soft clay foundation featured with the low shear wave velocity and high water content. The high - speed train could produce the big vibrations response to the saturated soft foundation. A slab track - saturated foundation coupled model was established to research the vibrations response to the saturated soil under the effect of the load of the high - speed train for the purposes of effectively overcoming the environment vibration induced by the high - speed train and proving the theoretical guidance to optimization of subgrade design of high - speed railway. Research conclusions： The numerical results show using the multiple -aperture saturated medium to simulate the saturated soil foundation can more accurately analyze the vibration response induced by the high -speed train, enhancing the track stiffness can effectively control the rail displacement and increasing the thickness of the foundation bed in design can reduce the impact of the liquid phase medium in soil on the dynamic response to the soil.