库坝渗漏隐患的自然电场三维正演及时空演化特征  

Three-dimensional forward modeling and temporal and spatial evolution characteristics of self-potential field of reservoir dam leakage hidden danger

作　　者：何尚富 邓居智[1,2,3] 刘遂明 陈辉 陈煜烽[1,3] 高江林 王烁 余辉 张国昆 李焱[1,2,3] HE ShangFu;DENG JuZhi;LIU SuiMing;CHEN Hui;CHEN YuFeng;GAO JiangLin;WANG Shuo;YU Hui;ZHANG GuoKun;LI Yan(State Key Laboratory of Nuclear Resources and Environment,East China University of Technology,Nanchang 330013,China;Engineering Research Center for Seismic Disaster Prevention and Engineering Geological Disaster Detection of Jiangxi Province,Nanchang 330013,China;School of Geophysics and Measurement-control Technology,East China University of Technology,Nanchang 330013,China;Jiangxi Academy of Water Science Engineering,Nanchang 330013,China)

机构地区：[1]核资源与环境国家重点实验室(东华理工大学),南昌330013 [2]江西省防震减灾与工程地质灾害探测工程研究中心(东华理工大学),南昌330013 [3]东华理工大学地球物理与测控技术学院,南昌330013 [4]江西省水利科学院,南昌330013

出　　处：《地球物理学进展》2023年第6期2392-2408,共17页Progress in Geophysics

基　　金：国家自然科学基金项目(42130811);核资源与环境国家重点实验室联合创新基金项目(2022NRE-LH-08);东方地球物理勘探有限责任公司委托项目“三维自然电位测量与放射性物探技术研究”(DFWT-2HWHTC-2022-JS-53);江西省“科技+水利”联合计划项目(2022KSG01003);江西省水利科学院开放研究基金项目(2022SKLS04)联合资助。

摘　　要：为了提高自然电场法监测技术在水库堤坝渗漏隐患方面的探测和监测作用,本文从库坝渗漏自然电场形成机理出发,推导了考虑水流场和离子扩散场的自然电场耦合方程,通过有限元-无限元方法实现了库坝自然电场三维数值模拟,开展了渗漏不同几何形态、不同水库水位及渗漏发育过程自然电场的响应特征研究.数值模拟结果表明:库坝自然电场的电位、电场(Ex和Ey)均受渗漏通道几何形态的变化而改变;自然电位极值随渗漏截面积及水位差增大均呈线性增加,随渗漏口位置下降而不断减小;在堤坝渗漏隐患初始-成长-渗漏-扩大四个演化过程中电位、Ex、Ey逐渐增大,渗漏其产生明显的异常信号,并在扩大期得到进一步增强.为此,在堤坝开展自然电磁探测和监测能够有效确定渗漏点位置和发育过程,对用于堤坝渗漏隐患演化和预测具有指导意义.Self-potential field coupling equation is derived for water flow field and ion diffusion field from the formation mechanism of the self-potential field.Reservoir dam leakage models with different geometric shapes of seepage,different reservoir water levels and different evolution periods are simulated numerically to research response characteristics of the self-potential field by finite element-infinite element method in order to improve the function of self-potential field monitoring technology in reservoir dam leakage hazards.Numerical simulation results show that the self-potential,Ex and Ey are all changed by the change of the geometry of the leakage;The extreme value of self-potential increases linearly with the increase of leakage cross-sectional area and water level difference,it decreases with the decrease of leakage position;In the leakage period of hidden danger development,self-potential,Ex and Ey increased obviously.It has guiding significance for the space-time evolution and prediction of dam leakage hidden danger,through reasonably arranging measuring electrodes to continuously monitor the self-potential field of dam.

关 键 词：自然电场 渗漏隐患 有限元-无限元 三维正演 

分 类 号：P319[天文地球—固体地球物理学]