高铁波场等效震源时间函数反演方法研究

Inversion of Effective Source Time Function of the High-Speed-Rail Wavefield

基于桥墩均匀分布且高铁列车匀速行驶情况下,每个桥墩源的震源时间函数仅存在时间延迟差异的假设,分别通过构建均匀空间声波模型以及半无限空间弹性波模型,计算格林函数,给出反演所用的线性方程组。利用最小二乘法对高铁波场的等效震源时间函数进行反演,测试在一定噪声水平下的反演效果,探讨各种因素对反演结果的影响。

Based on the assumption that there is only time delay difference in the source time function of each pier when the piers are uniformly distributed and the high-speed train moves at a uniform speed, we calculate Green’s function by constructing uniform spatial acoustic wave model and semi-infinite spatial elastic wave model, respectively, and give the linear equations used for inversion. Then the least square method is used to invert the effective source time function of the high-speed rail. For checking availability of the inversion method, the effect of inversion at a certain noise level is tested, and the influence of various factors on the inversion results is discussed.