高速列车运行引起的地表振动分析

把轨道作为弹性地基上的梁，得到轨枕与道床之间的动反力，采用薄层法求得分层土体的稳态响应，建立了运行车辆-轨道-环境振动模型，首次对秦沈高速铁路列车运行产生的沿线地基的振动响应进行了分析与对比．分析表明：移动轴重作用率对加速度频谱起控制作用，在其附近出现峰值；加速度随列车速度的提高缓慢增加，当列车速度接近地表的瑞利波速时，会引起振动放大现象；理论模型能很好地预测近场的振动响应．

Analysis of Ground Vibration Induced by High-Speed Train

The force between the sleeper and the ground is derived from the deflection curved of track.The track is modeled as a beam on an elastic foundation.The Green's function of a layered halfspace is obtained by the thin layer method(TLM) and the vibration model of moving train-track-environment is examined.Based on the measured data of the Qin-Shen rail line,the vertical ground vibrations from the track are analyzed.The theoretical results are validated by means of in-situ vibration measurements during the passage of a Xian-Feng high-speed train on the track of Qin-Shen.The validation indicates that the acceleration spectrum reaches the maximum at the fundamental axle passage frequency.The acceleration depends weakly on the train speed when it is lower than the Rayleigh wave velocity of the surface layer.A vibration boom is found when the train speed reaches the Rayleigh wave velocity.The vibration is well predicated in the near field.