桥梁预应力管道探地雷达定位及数据处理研究  

Research on Location and Data Processing of Ground Penetrating Radar for Prestressed Pipe in Bridges

作　　者：陈海涛 林聪 Chen Haitao;Lin Cong(China Railway Bridge Science Research Institute,Ltd.,Wuhan HuBei 430034,China;State Key Laboratory for Health and Safety of Bridge Structures,China Railway Bridge Bureau,Wuhan HuBei 430034,China)

机构地区：[1]中铁大桥科学研究院有限公司,湖北武汉430034 [2]中铁大桥局桥梁结构健康与安全国家重点实验室,湖北武汉430034

出　　处：《工程地球物理学报》2020年第1期101-106,共6页Chinese Journal of Engineering Geophysics

摘　　要：探地雷达技术是桥梁预应力管道定位的重要手段。在复杂条件下,雷达原始剖面分辨率降低、宜观性较差,不能确定预应力管道的实际位置,需要进行进一步的数据处理。反褶积技术通过压缩雷达子波延续时间可抑制预应力管道外侧钢筋引起的多次反射波,这不仅能够在很大程度上提高探地雷达图像的时间分辨率,还有助于识别来自深部预应力管道的反射特征;克希霍夫偏移通过将分散于双曲线两叶的能量汇聚于其顶部来提高雷达剖面的空间分辨率,经过处理后的雷达剖面能为准确找到预应力管道中心位置提供可靠依据。结合某混凝土桥梁实例说明了探地雷达在预应力管道定位中的应用,并对原始雷达剖面中经过反褶积与克希霍夫偏移处理后才发现的15根预应力管道进行了钻孔验证,验证结果与实际情况吻合,说明探地雷达定位误差小于2 cm,适用于桥梁预应力管道定位。Ground penetrating radar(GPR)technology is an important means of locating prestressed pipe in bridges.However,under complex conditions,the resolution of original radar profile is reduced and the visibility is poor,so the actual location of prestressed pipe cannot be determined,and further data processing is required.The deconvolution technique can suppress the multiple reflection waves caused by the outer rebar of the prestressed pipe through the compression of the extension time of radar wavelet,which can not only improve the time resolution of GPR image to a large extent,but also help to identify the reflection characteristics from the deep prestressed pipe.The Kirchhoff migration improves the spatial resolution of the radar profile by concentrating the energy scattered between the hyperbolic blades at its top,and the original radar profile after processing can provide a reliable basis for accurately locating the center of prestressed pipe.In this paper,the application of ground penetrating radar in locating prestressed pipe is illustrated with a concrete bridge example where the drilling verification of 15 prestressed pipes found in original radar profile after deconvolution and Kirchhoff migration is carried out.The verification results are consistent with the actual situation,indicating that the locating error of GPR is less than 2cm,which is suitable for the locating of prestressed pipe in bridges.

关 键 词：探地雷达 预应力管道 数据处理 反褶积 克希霍夫偏移 

分 类 号：P631.3[天文地球—地质矿产勘探]