基于瞬变电磁法的均质土坝渗漏通道探测与消险质量评价  

Detection and Quality Assessment of Homogeneous Dam Leakage Channel Based on the Transient Electromagnetic Method

作　　者：张盛行 汤雷[1] 朱春光 石蓝星 明攀 ZHANG Shenghang;TANG Lei;ZHU Chunguang;SHI Lanxing;MING Pan(Nanjing Hydraulic Research Institute,Nanjing,Jiangsu 210024,China;Nanjing Yangtze River Management Office,Nanjing,Jiangsu 210011,China)

机构地区：[1]南京水利科学研究院,江苏南京210024 [2]南京市长江河道管理处,江苏南京210011

出　　处：《水利与建筑工程学报》2025年第2期98-105,共8页Journal of Water Resources and Architectural Engineering

基　　金：国家重点研发计划(2021YFC3090103);南京市水务科技项目(202404);广东省水利科技项目(RS2023-02)。

摘　　要：瞬变电磁法具有对探测目标电阻率差异敏感的特点,逐渐应用于土石坝渗漏通道探测。基于均质土坝地电特性,建立瞬变电磁探测的三维有限元模型,分析均质土坝有、无渗漏通道时的典型响应,对比烟圈和最小二乘反演算法的适用性,并在均质土坝实际消险工程中应用。结果表明:测量曲线能够反映出坝体内部电阻分布特征;相比于烟圈成像,最小二乘反演算法反演土石坝内部渗漏低阻区的位置和范围更加准确;结合钻孔验证,该方法能够较为准确地定位出基岩界面、渗漏通道等区域;通过均质土坝消险前、后探测所得的视电阻变化情况,能够反映大坝内部渗漏通道的修复效果,可为探测渗漏通道与评价消险质量提供参考。The transient electromagnetic method which is highly sensitive to the resistivity variance of detection targets,has been increasingly applied to the detection of seepage channels in earth-rock dams.A three-dimensional finite element model for transient electromagnetic detection is established based on the geoelectric characteristics of a homogeneous dam,and the typical responses of a homogeneous dam with or without leakage channels are obtained.The applicability of the smoke ring and least squares inversion algorithms is compared,and it is utilized in the actual homogeneous dam hazard elimination project.The results indicate that the transient electromagnetic method can reflect the characteristics of the apparent resistivity within the homogeneous dam.Compared with smoke ring imaging,the least squares inversion algorithm is more precise in retrieving the location and scope of the low-resistance area of seepage in the earth-rock dam.Combined with drilling verification,this method can more accurately locate the bedrock interface and leakage channel.The variation of apparent resistance detected before and after the removal of the homogeneous dam can be employed to predict the repair of the seepage channel inside the dam and the anti-seepage performance of the dam body,providing a reference for the quality assessment.

关 键 词：均质土坝 渗漏探测 瞬变电磁法 正演模拟 反演方法 消险质量评价 

分 类 号：TV641[水利工程—水利水电工程]