降雨条件下排土场边坡损伤的电阻率变化特征研究  

Studyonthe Resistivity Variation Characteristics of Dump Slope Damage Under Rainfall Conditions

作　　者：康恩胜 孟海东 杜鹏东 赵泽熙 赵自豪 郑清旭 KANG Ensheng;MENG Haidong;DU Pengdong;ZHAO Zexi;ZHAO Zihao;ZHENG Qingxu(School of mining and coal,Inner Mongolia University of Science and Technology,Baotou,Inner Mongolia014010,China;School of Resources and Civil Engineering,Northeastern University,Shenyang,Liaoning 110819,China)

机构地区：[1]内蒙古科技大学矿业与煤炭学院,内蒙古包头市014010 [2]东北大学资源与土木工程学院,辽宁沈阳110819

出　　处：《矿业研究与开发》2023年第9期51-61,共11页Mining Research and Development

基　　金：内蒙古自治区高等学校科学技术研究项目(NJZY19127);内蒙古自治区自然科学基金项目(2019MS04016)。

摘　　要：为了研究降雨条件下排土场边坡的损伤破坏,设计了降雨渗流条件下的排土场边坡模型。根据岩土体三相介质理论和麦克斯韦电导率公式,对降雨边坡损伤电阻率变化进行了研究,推导了同时考虑宏观与微观变化的降雨边坡损伤-电阻率-孔隙率的关系表达式,与Archie公式对比验证了模型的合理性。采用高密度电阻率法测量不同降雨时刻的边坡岩土体视电阻率,反演了降雨边坡内部损伤的形成过程。对比了不同含水率条件下的边坡视电阻率变化,依据岩土体电阻率理论分析了降雨边坡软弱面和裂隙发育的视电阻率变化特征。试验结果表明,降雨条件下排土场边坡岩土体为非饱和—饱和的动态循环过程;视电阻率与边坡内孔隙和裂隙中的含水率呈负相关关系,水分入渗过程中的视电阻率降低,裂隙发育过程中的视电阻率升高;在边坡损伤破坏过程中,视电阻率在裂隙发育和水分渗流耦合作用下发生改变,原有“缺陷”点邻近区域的视电阻率发生突变和波动;突变多发生于“缺陷”点邻近区域渗流饱和后的干湿循环过程,可以依据探测所得视电阻率突变和异常波动判断边坡内部的损伤情况。In order to study the damage and failure of dump slope under rainfall conditions,a dump slope model under rainfall seepage conditions was designed.According to the three-phase medium theory of rock-soil mass and Maxwell's conductivity formula,the variation of damage resistivity of rainfall slope was studied,the relationship expression of damage-resistivityporosity of rainfall slope considering both macro and micro changes was derived.The rationality of the model was verified by comparing with Archie formula.The apparent resistivity of rock-soil mass of slope at different rainfall times was measured by high density resistivity method,and the formation process of internal damage of rainfall slope was inverted.The variation of apparent resistivity of slope under different water content conditions was compared.According to the resistivity theory of rocksoil mass,the variation characteristics of apparent resistivity of weak surface and fracture development of rainfall slope were analyzed.The test results show that the rock-soil mass of the dump slope is an unsaturated-saturated dynamic cycle process under the condition of rainfall.The apparent resistivity is negatively correlated with the water content in the pores and fractures in the slope.The apparent resistivity decreases during water infiltration and increases during crack development.In the process of slope damage and failure,the apparent resistivity changes under the coupling effect of fracture development and water seepage,and the apparent resistivity of the adjacent area of the original"defect"point changes and fluctuates.The abrupt change mostly occurs in the dry-wet cycle process after the seepage saturation in the adjacent area of the"defect"point.The damage in the slope can be judged according to the abrupt change and abnormal fluctuation of the apparent resistivity detected.

关 键 词：排土场 边坡损伤 降雨渗流 高密度电阻率法 视电阻率 

分 类 号：TD804[矿业工程—矿山开采] P319.1[天文地球—固体地球物理学]