管道渗漏区探地雷达响应特征分析

Response Characteristics Analysis of Ground Penetrating Radar in Pipeline Leakage Area

探地雷达在供水管道渗漏区探测方面具有广阔的应用前景。为增强渗漏区探地雷达响应特征的认识,提高渗漏区定位精度,基于时域有限差分法,模拟金属管道底部渗漏的探地雷达响应特征,并提取“三瞬”地震属性进行分析。结果表明,渗漏区上边界信号易识别,内部信号存在多次反射和震荡现象;渗漏区瞬时振幅属性与原始剖面反映效果相似,瞬时相位属性同相轴错断明显,瞬时频率属性明显衰减;瞬时相位属性和瞬时频率属性对渗漏区的存在及微弱信号反映效果较好,故渗漏区瞬时属性分析时优选瞬时相位属性和瞬时频率属性。结果可为探地雷达管道渗漏区探测图像解译和实际工程应用提供参考。

Ground penetrating radar(GPR) has a broad application prospect in detecting the leakage area of water supply pipeline. In order to enhance the understanding of the response characteristics of GPR in the leakage area and improve the positioning accuracy of the leakage area, based on the finite difference time domain method, this paper simulated the response characteristics of ground penetrating radar for leakage at the bottom of metal pipes, and extracted the "three instantaneous" seismic attribution. The results show that the upper boundary signal of the leakage area is easy to be identified, and the internal signal has multiple reflections and oscillations. The reflection effect of the instantaneous amplitude attribution in the leakage area is similar to that of the original profile. The instantaneous phase attribution is obviously staggered, and the instantaneous frequency attribution is obviously attenuated. Instantaneous phase attribution and instantaneous frequency attribution can reflect the existence of leakage area and weak signal well, so the instantaneous phase attribution and instantaneous frequency attribution are preferred when analyzing the instantaneous attribution of leakage area. The research results can provide a reference for the interpretation of GPR pipeline leakage detection images and practical engineering applications.