用分层半空间上周期性支撑的欧拉梁模型求解多层地基和铁路轨道在列车运动荷载作用下的振动问题,通过Fourier积分变换得到轨道运动的格林函数表达式,并用矩阵传递法导出地基对轨枕的支撑刚度,结合轨道和地基运动的整体方程得到振动解。通过实例计算分析不同速度的列车在软土地基上运行时分层地基的波动特性和地基内部振动变形的分布规律,发现地基振动特性主要取决于列车的运行速度和地基的土层性状。
Dynamic responses of track structure and layered ground due to moving train loadings were studied with an elaborated model of an Euler beam resting on layered half-space with periodical contacts.The Green function solution of track vibration was obtained by means of Fourier transform;and the flexibility matrix of layered ground was deduced with the matrix transfer method.The analytical solution of the track and ground dynamic interaction was given by solving the integrated system equations.Track and ground responses were obtained both in frequency domain and time domain.An illustrative case study was conducted to reveal the characteristics of ground motions induced by high-speed train runnings on layered ground.Wave motions at ground surface and inside ground have been found strongly dependent on train’s moving speed and ground media properties.