摘要
隧道衬砌空洞易引发衬砌破坏、渗漏水等工程问题,但因衬砌内部金属(如钢筋、钢拱架)对雷达波的屏蔽作用,会增加雷达剖面的复杂性,进而影响检测效果。依托MATLAB软件平台,采用高阶时域有限差分法分别对400 MHz天线和900 MHz天线时隧道衬砌矩形空洞和三角形空洞进行正演模拟。结果表明:高阶时域有限差分法能高精度模拟雷达波在衬砌中的传播特性,展示衬砌中钢筋、空洞、工字钢的反射波、绕射波的能量、振幅、相位特征;900 MHz天线可分辨出长度在0.3 m及以上的界面,远高于400MHz天线的检测精度,但检测界面相对于真实界面小。
The cavities behind tunnel lining will cause damage,leakage and other engineering problems. Due to the metal（ such as steel and arch frame） in lining,the effect of radar wave will be influenced,which will increase the complexity of radar cross-section and affect the test results. The rectangular cavity and triangle cavity behind tunnel lining is forward simulated by high-grade finite difference time domain（ FDTD） method when using 400 MHz antenna and 900 MHz antenna based on MATLAB software platform. The results show that： 1） The propagation characteristics of radar wave in tunnel lining can be simulated accurately by high-grade finite difference time domain method. The reflection of signal of rebar,cavity and shaped steel can be shown and recognized. 2） The 900 MHz antenna can recognize boundary with length of larger than 0. 3 m,of which the detection precision is higher than that of 400 MHz antenna and the detection boundary is small than actual one.
出处
《隧道建设》
北大核心
2017年第A01期13-19,共7页
Tunnel Construction
关键词
隧道衬砌
空洞
探地雷达
高阶时域有限差分法
正演模拟
tunnel lining
cavity
ground penetrating radar
high-grade finite difference time domain method
forward modeling
