高速移动荷载下黏弹性半空间体的动力响应

分别以移动荷载和黏弹性半空间体模拟运动列车荷载和地基,分析了地基在运动列车作用下的动力响应.首先采用Green函数法求解黏弹性半空间体在各种移动荷载模式作用下的动力响应的解析解,包括恒常和简谐移动点源、线源和面源荷载.然后采用IFFT算法和自适应数值积分算法计算解析解中的二维积分,得到了包括低音速、跨音速和超音速移动荷载作用下位移的数值结果.最后分析了速度对位移的分布和最大值的影响,发现当速度大于Rayleigh波速时,位移发生显著变化.

DYNAMIC RESPONSE OF VISCOELASTIC HALF-SPACE UNDER MOVING LOADS

To investigate high-speed train induced subground vibrations,viscoelastic half-space under moving loads was used to model the subground under passing trains.Analytical solutions for displacements of the viscoelatic half-space were obtained using Green's function method for various moving loads,including constant and harmonic point,line and area load.All velocity cases including the subsonic,transonic and supersonic velocities were considered.Coupled IFFT algorithm and adaptive quadrature algorithm were employed to compute double integrals in the analytical solutions.Numerical results for displacements induced by constant moving point load were presented in this paper as examples.The effects of velocity on the distribution and the maximum value of displacements were discussed.It is found that the distribution and the maximum value of displacements vary significantly as velocity increases beyond Rayleigh wave speed.