秦－沈铁路列车运行引起的地面振动实测与分析

秦皇岛－沈阳铁路是国内一条快速客运专线, 2002年由铁道部组织了第2次综合试验，对垂直线路不同距离、不同行车速度下的地面振动进行了现场测试。首先分析了实测地面竖向振动加速度特征，重点讨论列车编组及行车速度对地面振动的影响。将轨道作为弹性地基上的梁，考虑轨枕的离散作用，建立了运行车辆-轨道-地面振动模型。基于薄层法原理，推导了柱坐标系下的二次形函数薄层法，求得分层土体的稳态响应，首次对秦皇岛－沈阳快速客运专线产生的地面振动进行了分析。结果表明：移动轴重作用率对加速度频谱起控制作用；因列车速度远小于地基的瑞利波速，故未出现地面振动放大现象；振动加速度与轮轴荷载呈线性增加趋势。

Experimental results and numerical predictions of ground vibration induced by high-speed train running on Qin-Shen Railway

Qin-Shen Railway is the first special passenger traffic line in China.In 2002,the Ministry of Railways organized the second homologation test.The authors performed the field vibration measurements at various distances from the track.Firstly,the field measured vertical accelerations are analyzed.The attention is paid on the effect of train organization and train speed on the ground vibration.Secondly,the track is modeled as a beam on an elastic foundation;the vibration model of moving train-track-ground is constructed.Based on the theory of thin layered method(TLM),the quadratic shape function TLM is derived.The Green function of a layered half-space is obtained.At last,the ground vibration from the track is analyzed and the result is validated by means of in-situ vibration measurements.The results show that the acceleration spectrum has a maximum at the fundamental axle passage frequency.Vibration amplification is not appeared because the trains speed far less than the Ralyeigh wave velocity of the ground.The vibration acceleration is proportion to the wheel load.