砂岩体裂隙渗流区的探地雷达信号动态响应机制  

Dynamic response mechanism of radar wave propagation characteristics to fracture seepage in sandstone

作　　者：安娅菲 冯晅[1] 董泽君[1] 周皓秋 张明贺[1] 杨佳润 张英浩 AN Yafei;FENG Xuan;DONG Zejun;ZHOU Haoqiu;ZHANG Minghe;YANG Jiarun;ZHANG Yinghao(College of Geoexploration Science and Technology,Jilin University,Changchun 130000,P.R.China)

机构地区：[1]吉林大学地球探测科学与技术学院,长春130000

出　　处：《重庆大学学报》2024年第10期181-190,共10页Journal of Chongqing University

基　　金：国家重点研发计划资助项目(2021YFC1523401);吉林省教育厅优秀青年项目(JJKH20241253KJ)。

摘　　要：裂隙病害是石窟寺较为普遍而广泛存在的病害类型,水的参与加速了石窟岩体中裂隙的发育,裂隙渗流成为文物保护中的一项难题。针对石窟寺裂隙渗流问题,研究了雷达波地下传播特征对砂岩体裂隙渗流的动态响应机制。首先,依据实际物性参数和Richards方程建立了砂岩体裂隙渗流的瞬态模型;再采用时域有限差分法,对砂岩裂隙渗流模型进行探地雷达波场数值模拟;最后,利用Hilbert变换进行瞬时属性的提取,分析不同渗流时间下的雷达波场响应特征。砂岩体裂隙渗流模拟发现,裂隙渗流使得岩体渗流区域的介电常数增大,增强了该区域对雷达波的散射,导致雷达波散射的瞬时振幅随含水饱和度增大而增大。研究结果为探地雷达实现超精度探测砂岩体微小渗流裂隙提供了重要的理论支撑。Fracture-related deterioration is common in grottoe temple rock masses,with water seepage exacerbating the issue,complicating cultural relic preservation.This study explores the dynamic response mechanism of radar wave propagation to fracture seepage in sandstone.Firstly,a transient model,based on physical parameters and Richards equation,is established.Then,the finite difference time domain method is used to numerically simulate the fractured seepage in sandstone with ground-penetrating radar(GPR).Finally,Hilbert transform is used to extract the instantaneous attributes and analyze the radar wave field responses under different seepage durations.Simulation of sandstone fracture seepage reveals that fracture seepage increases the dielectric constant of seepage area,enhances radar wave scattering in this area,and causes the instantaneous amplitude of the radar wave scattering to increase with the increase of water saturation.The reselts provide an important theoretical support for GPR in detecting micro-seepage fractures in sandstone.

关 键 词：探地雷达 裂隙渗流 水文模拟 瞬时属性 

分 类 号：TN957[电子电信—信号与信息处理]