隧道衬砌内部空洞探测的FDTD正演模拟与试验研究  

FDTD Forward Simulation and Experimental Study of Tunnel Lining Internal Cavity Detection

作　　者：杨成忠[1] 罗坤 王威 陈屹林 YANG Cheng-zhong;LUO Kun;WANG Wei;CHEN Yi-lin(Civil Engineering College,East China Jiaotong University,Nanchang 330013,China)

机构地区：[1]华东交通大学土木建筑学院,南昌330013

出　　处：《铁道标准设计》2018年第11期114-117,124,共5页Railway Standard Design

基　　金：国家自然科学基金(51668017);江西省自然科学基金(20152ACB20016);江西省交通运输厅科技项目(2016D0038)

摘　　要：针对隧道衬砌内部空洞缺陷,基于时域有限差分(FDTD)法,对探地雷达电磁波在空洞缺陷衬砌内的传播过程进行正演模拟,分析空洞横向直径变化对电磁波反射响应特征影响,进而设计两类不同尺寸的空洞模型,测试探地雷达在规则空洞的反射响应特征。结果表明:随着空洞横向直径的增大,正演合成图显示的空洞反射响应特征表现为由双曲线逐步向矩形变化,探地雷达实测规则空洞的反射响应特征为双曲线,与正演模拟结果一致,为识别雷达图谱提供有效的支持,提高后续解译的可靠性,为地质雷达探测隧道衬砌内部空洞缺陷的结果提供可靠的解释依据。Based on the Finite-Difference Time-Domain （ FDTD ） method, the propagation ofelectromagnetic wave of ground penetrating radar （ GPR） in the cavity defect lining is simulated byforward modeling method to solve the inner cavity deficiency in tunnel lining. The influence of thevariation of the cavities＇ lateral diameters of the cavity on the reflection response of the electromagneticwave is analyzed. Then two kinds of cavity models with different sizes are designed to test the reflectionresponse characteristics of the ground penetrating radar detecting in the regular cavity. The results showthat as the transverse diameters of the cavities increase, the reflection response of the cavity shown by theforward composite diagram changes from hyperbola to rectangle, and the reflection response of the regularcavity measured by the ground penetrating radar is in the form of hyperbola, which accords with theforward modeling results. Thus, effective support is provided for the identification of radar images, thereliability of subsequent interpretation is improved, and reliable interpretation basis is laid for assessingthe results of GPR detection.

关 键 词：隧道 衬砌 空洞缺陷 探地雷达 正演模拟 FDTD法 

分 类 号：U456.3[建筑科学—桥梁与隧道工程]