探地雷达检测铁路路基病害的二维正演模拟  

Two-dimensional forward simulation of railway roadbed disease based on ground penetrating radar technique

作　　者：谢勇勇[1] 廖红建[1] 昝月稳[2] 

机构地区：[1]西安交通大学土木工程系,陕西西安710049 [2]西安铁路局科学技术研究所,陕西西安710049

出　　处：《浙江大学学报（工学版）》2010年第10期1907-1911,共5页Journal of Zhejiang University：Engineering Science

基　　金：国家自然科学基金资助项目(50979087)

摘　　要：为了识别复杂的探地雷达图像,建立铁路路基病害图像数据库,针对各种常见的路基病害,结合实地检测情况,研究铁路路基病害的探地雷达(GPR)图像特征,进行探地雷达二维正演模拟分析.基于有限差分原理,在时间域上推导横电磁波的差分方程;运用GprMax软件,对路基下道碴陷槽病害进行正演模拟分析;对路基下存在的圆形空洞,模拟不同半径和埋深的空洞,分析径深比对雷达模拟图像的影响.开挖一个人工道碴陷槽,用探地雷达实测,并进行正演模拟.实测结果和模拟结果一致,表明了该模拟方法用于实际复杂路基检测的可行性.An image database for railway track anomalies was established to identify the complicated ground penetrating radar （GPR） images. The characteristics of GPR images were analyzed and the twodimensional forward modeling was conducted considering all kinds of common track deteriorations and combining field measurement results. The difference equation for the transverse electromagnetic wave in time domain was derived based on the finite difference method. The forward simulation was conducted for trapped ballast pockets by using the GprMax. Different radiuses and depths of the cavities were simulated for circular cavities under the track, and their effects on the simulated GPR images were analyzed. An artificial rectangular ballast pit was constructed and inspected by GPR. Numerical modeling was conducted. The measured results accorded with the simulated images, which indicated that the simulation for GPR can be applied to simulate actual railway track conditions.

关 键 词：探地雷达 二维正演模拟 时域有限差分 铁路病害 

分 类 号：U212.4[交通运输工程—道路与铁道工程] U216.3