基于瞬变电磁雷达的检测技术及其在隧道衬砌中的应用

基于自主研发的瞬变电磁雷达技术对铁路隧道衬砌质量进行检测，结合双极性叠加法与小波去噪法对采集信号作去噪处理，利用欠阻尼探测天线，得到隧道衬砌各部位缺陷特征；结合地质雷达（GPR）检测和现场钻孔数据，通过典型图像分析，对比瞬变电磁雷达在探测深度、图像分辨率方面与地质雷达的差异，总结其相对于普通衬砌检测雷达所具有的优势。综合分析表明，瞬变电磁雷达应用于衬砌检测具有如下特性：（1）探测深度较大，穿透性较强；（2）图像分辨率较高，电磁波反射具有体积效应，成像直观清晰；（3）操作更便捷，雷达主机与采集终端为无线数据传输且设备轻便，可单人操作，数据可现场处理，从而可快速实时查看隧道衬砌缺陷，并标定衬砌缺陷部位便于后续处理。

Detection Technology Based on Transient Electromagnetic Radar and Its Application in Tunnel Lining

Based on the self-developed transient electromagnetic radar technology, the quality of railway tunnel lining was detected. The bipolar superposition method and wavelet denoising method were combined to denoise the collected signals, and the underdamped detection antenna was used to obtain the defects of various parts of the tunnel lining. Combining geological radar (GPR) detection and on-site drilling data, the typical image analysis was used to compare the difference of detection depth and image resolution between transient electromagnetic radar and geological radar, and summarize its advantages over ordinary lining detection radar. The comprehensive analysis shows that the transient electromagnetic radar applied to the lining detection has the following characteristics: (1) the detection depth is large and the penetration is strong; (2) the image resolution is high, the electromagnetic wave reflection has volume effect, and the imaging is intuitive and clear; (3) the operation is more convenient, the radar host and the collection terminal are wireless data transmission and the equipment is light thus single person can operate it, and the data can be processed on site, so that the tunnel lining defects can be quickly and real-time viewed, and the lining defect parts can be calibrated for subsequent processing.