管线模型的探地雷达物理模拟实验  

Ground penetrating radar physical simulation experiment of pipeline model

作　　者：杨军 李婷 袁忠明 柳杰 苏玄 冯德山[2] 王珣[2] 丁思元 张华 刘硕 YANG Jun;LI Ting;YUAN ZhongMing;LIU Jie;SU Xuan;FENG DeShan;WANG Xun;DING SiYuan;ZHANG Hua;LIU Shuo(Guangzhou Municipal Engineering Design and Research Institute Co.,Ltd.,Guangzhou 510060,China;School of Geosciences and InfoPhysics,Central South University,Changsha 410083,China)

机构地区：[1]广州市市政工程设计研究总院有限公司,广州510060 [2]中南大学地球科学与信息物理学院,长沙410083

出　　处：《地球物理学进展》2023年第2期912-927,共16页Progress in Geophysics

基　　金：国家自然科学基金资助项目(41774132);广州市市政工程设计研究总院有限公司重大攻关资助项目(1-43010100)联合资助。

摘　　要：地下管线是保障城市运行的重要基础设施与生命线,开展管线探测是城市地下工程建设中必不可少的环节.探地雷达正演有助于掌握雷达波在地下的传播规律、加深对管线回波的认识.由于真实的地下介质分布不均匀、测区环境充斥着多种干扰,导致实际的探地雷达剖面中回波信号成分复杂、目标双曲线形态不完整,难以直接进行地质解释,而数值模拟常不考虑杂波干扰,模拟结果相对理想化.因此,本文聚焦于管线模型的物理模拟实验,在室内实验室和野外现场构建了一系列不同材质、不同埋深、不同管径的管线模型,利用不同中心频率的天线开展探测实验;分析了地下管线的雷达波传播规律及特征;结合管线材质、大小和埋深等信息,进一步验证雷达资料解释的准确度.结果表明:在背景介质均匀的沙池实验中,原始雷达剖面中背景噪声较小、目标双曲线形态完整,金属管线的反射波能量最强,含水管线会引起明显的多次波.而在野外现场采集到的雷达数据中存在较多的噪声干扰,不同管线引起的雷达回波呈双曲线或“类双曲线”;与背景介电常数的差异越大,反射波能量越强;相较于深埋管线,浅埋管线的双曲线特征更明显、振幅能量更强.由此可见,不同管线具有不同的双曲线特征、相位和振幅特征,可为地下管线普查和管线检测资料解译提供理论依据.Urban underground pipelines are an important infrastructure and lifeline to ensure urban operation, and pipeline detection is an indispensable link in the construction of urban underground projects. Ground Penetrating Radar(GPR)forward modeling is helpful to grasp the propagation law of radar waves in the underground medium and deepen the understanding of the pipeline echo waveform. Due to the uneven distribution of the real underground media and the environment of the measurement area, the echo signal composition in the actual GPR profile is complex, the target hyperbolic form is incomplete, which is difficult to directly interpret the geological interpretation. While the numerical simulation often does not consider the clutter interference, and the simulation results are relatively idealized. In this paper, we focuse on the physical simulation of the pipeline model, and constructs a series of pipeline models of different materials, different burial depths and different pipe diameters in the laboratory and the field, and uses antennas with different center frequencies to carry out detection experiments. The propagation law and characteristics of radar waves of underground pipelines are analyzed. Combined with the actual pipeline material, size and burial depth information, the accuracy of data interpretation is further verified. The results show that the background noise in the original GPR profile is small, the target hyperbola morphology is complete, the reflected wave energy of the metal pipeline is the strongest, and the pipeline filled with water will cause obvious multiple waves. However, there is more noise interference in the GPR data collected in the field, and the radar echo caused by different pipelines is hyperbolic or “hyperbolic”. In addition, the greater the difference of dielectric constant between pipeline and background medium, the stronger the reflected wave energy. Compared with the deep pipeline, the hyperbolic characteristics of the shallow pipeline are more obvious and the amplitude en

关 键 词：探地雷达 管线探测 雷达剖面特征 物理模拟 野外测量 

分 类 号：P631[天文地球—地质矿产勘探]