中文摘要：

基于比例边界有限元法与傅里叶积分变换,分析移动荷载作用下半无限弹性空间中地铁隧道动力响应。考虑到移动荷载运动方向与地铁隧道轴线方向的一致性,将半无限弹性空间动力控制方程进行频域—波数域的傅里叶积分变换;在变换域内,隧道径向采用比例坐标系,环向采用有限元意义离散,在计算域内利用Galerkin法,建立频域—波数域内的比例边界有限元方程,进而推导出半无限空间动力刚度的一阶微分矩阵方程;再利用高频渐近展开和傅里叶积分逆变换,得到时间—空间域系统的动力响应。该方法极大地减小了计算分析量,同时避免了无限边界的计算误差。利用该方法进行实例计算的结果表明：随着荷载移动速度的增大,地铁隧道振动波传播到土体表面,引起的土体振动有放大增强的现象,将会对地铁隧道上部结构的安全性造成一定影响。

英文摘要：

The dynamic response of metro tunnel under moving load in semi-infinite elastic space was analyzed by using scaled boundary finite element method and the Fourier integral transform.Considering the consistency between the direction of moving load and the axis of metro tunnel,the dynamic governing equations in semi-infinite elastic space were deduced with the Fourier integral transform in frequency-wave domain.Proportional coordinate system was adopted for the radial direction of tunnel and FE discretization for the circumferential direction of tunnel in transform domain.The Galerkin＇s weighted residual method was used in computational domain to establish the scaled boundary finite element equations in frequencywave domain and then the first-order differential matrix equation of dynamic stiffness in semi-infinite elastic space was deduced.The dynamic response in time-space domain was obtained by means of high frequency asymptotic expansion and Fourier integral inverse transform.The proposed method has greatly reduced computational analysis.At the same time,the calculation error of infinite boundary is avoided.Example calculation results show that,with the increase of load moving speed,the vibration wave of metro tunnel propagates to soil surface and results in the amplification and enhancement of soil vibration,which will cause certain impact on the safety of the superstructure of subway tunnel.