参数化分析列车运行产生的路堤–地基振动

 为预测和分析高速列车运行产生的轨道和路堤振动及波动在沿线周围地基中的传播，利用2.5维有限元方法建立了轨道、路堤和下卧层地基在移动荷载作用下的动力耦合分析模型及无路堤情况下的轨道地基模型，求解三维地基的动力响应。对高速或低速运行的列车多轮重荷载产生的路堤和地基振动进行对比分析。通过参数化分析明确轨道刚度、路堤高度、地基土的剪切波速及阻尼系数、列车速度和振动频率等参数对地基振动和传播特性的影响。给出的方法和结论可用于分析软土地基上运行高速列车时的稳定性问题和评估列车运行对周围环境的振动影响。

PARAMETRIC STUDY ON EMBANKMENT-GROUND VIBRATIONS GENERATED BY TRAIN MOVING LOADS

In order to predict and evaluate track and embankment vibrations generated by train moving load and wave propagation in adjoining ground，a coupled dynamic interaction model for track and underlying ground under moving loads was developed by employing the 2.5D finite element method，and dynamic responses of three-dimensional ground were obtained. Multi-wheel axle train loadings were considered to study the track and ground vibrations both for low-speed and high-speed cases；and computation results were illustrated to show the ground response characteristics. Extensive parametric studies were performed to assess influences of several controlling parameters，including track stiffness，embankment height，shear wave velocity and damping ratio of underlying ground soil，train speed and its vibration frequency. The analytical results obtained in the current study are important to analyze the running stability of high-speed train on soft soil ground and to evaluate its vibration impact to adjoining ground along raillines.