凸起地形对铁路环境振动的影响分析

建立了列车作用下路基-凸起地形的二维有限元计算模型，研究了凸起地形宽度、形状、高宽比以及地基土性质对铁路环境振动的影响规律。结果表明，凸起地形减弱了铁路环境振动的地面加速度，明显放大了水平振动位移，对竖向振动位移的影响不明显；随凸起地形宽度、高宽比的增大，水平振动位移的放大效应更为显著；高宽比越大，竖向、水平两个方向地面加速度减小越明显；半圆形、梯形凸起地形对铁路环境振动的影响较为一致，但三角形凸起地形的水平地面加速度在凸起地形顶部出现明显的局部放大，水平振动位移的放大效应较半圆形、梯形地形要明显；地基愈软弱，凸起地形的影响效应越显著。

Influence of hill on railway environmental vibration

A two-dimensional finite element calculation model of subgrade-hill under the vibration of train is established, and the influence of the width, shape, aspect ratio of hill and soil properties on railway environmental vibration is studied. The result shows that the ground acceleration of railway environmental vibration is reduced, but the horizontal vibration displacement is significantly amplified, and the influence on vertical vibration displacement is not obvious. With the increase of the width and aspect ratio of the hill, the amplification effect of horizontal vibration displacement becomes notable. The larger the aspect ratio is, the more obvious the vertical and horizontal ground accelerations decrease. The influence of semicircular and trapezoidal hill on railway environmental vibration is consistent, but the horizontal acceleration at the top of the triangular hill is locally amplified, and the amplification effect of horizontal vibration displacement is more obvious than that of the trapezoidal and semicircular hills. When the soil is soft, the effect of the hill becomes significant.