摘要
土石坝渗漏问题是制约水库大坝安全运行的重要隐患,准确查明大坝渗漏的病因以及靶区的空间展布是有的放矢实施加固的关键.针对土石坝隐患的空间位置信息多变、周围介质复杂等难点,单一探测手段在识别病灶方面存在误判、漏判等问题,考虑到电阻率对水敏感的特点,提出联合并行电法和瞬变电磁法优化诊断土石坝渗漏隐患的思路.为查明戴家坞水库渗漏的病灶,利用并行电法快速获得大坝坝体段不同高程下的二维视电阻率图像,分析比较了AMN、MNB以及AMN&MNB装置的反演结果,还采用瞬变电磁法对大坝两坝肩并行电法盲区部位进行补充探测,并依据成果进行防渗处理.试验结果表明,并行电法有效指示出大坝坝体段的渗流异常,综合多剖面异常信息能追踪到渗漏路径;AMN&MNB装置的反演结果有效吸收了AMN、MNB的局部高分辨的优势,对大坝边界以及隐患规模的细节刻画更清晰;结合二次场响应曲线和视电阻率图像,瞬变电磁法很好揭示出大坝坝肩K0-005~0+002 m段的渗漏通道,同时有效规避了硬化路面电极接触不良的难题.经对综合推断隐患区进行灌浆处理,大坝渗漏量明显降低,从而佐证了两种方法优化联合的可行性.研究成果可为水库大坝隐患的全面、精细探查提供技术支撑.
The leakage of embankment dam is an important hidden danger that restricts the safe operation of the reservoir.Accurately identifying the cause of dam leakage and the spatial distribution of the target area are the key to the targeted reinforcement.Due to the variable spatial location information of the hidden danger of embankment dam and the complexity of the surrounding media,a single detection method has problems such as misjudgment and omission in identifying the lesion.Considering the characteristic that the resistivity is sensitive to water,the idea of joint parallel electric method and Transient Electromagnetic Method(TEM)to optimize the diagnosis of hidden trouble of embankment dam is proposed.In order to find out the leakage of Daijiawu Reservoir,the Parallel Electrical Method was used to quickly obtain two-dimensional apparent resistivity images of the dam body section at different elevations.The inversion results of AMN,MNB,and AMN&MNB were analyzed and compared.The Transient Electromagnetic Method is used as a supplemental detection for the blind areas of the two dam abutments with Parallel Electrical Methods,and the seepage prevention treatment is carried out according to the results The results show that the Parallel Electrical Method effectively indicates the seepage anomaly of the dam body section,and the comprehensive multi-profile anomaly information can track the leakage path;the inversion results of the AMN&MNB array effectively absorb the local high-resolution advantages of AMN and MNB.The detailed description of the dam boundary and the scale of hidden dangers is clearer;combined with the secondary field response curve and the apparent resistivity image,TEM can well reveal the leakage channel of the dam abutment K0-005~0+002 m.At the same time,it effectively avoids the problem of poor contact between hardened road electrodes.After grouting the hidden danger area,the leakage of the dam was significantly reduced,which proved the feasibility of the optimization and combination of the two methods.The research result can provide technical support for comprehensive and precise exploration of hidden dangers of reservoirs.
作者
赵汉金
江晓益
韩君良
谭磊
ZHAO Hanjin;JIANG XiaoYi;HAN JunLiang;TAN Lei(Zhejiang Geology and Mineral Construction Co.,Ltd.,Hangzhou 310053,China;Zhejiang Institute of Hydraulics and Estuary(Zhejiang Institute of Marine Planning and Design),Hangzhou 310020,China;Zhejiang Provincial Key Laboratory of Water Conservancy Disaster Prevention and Reduction,Hangzhou 310020,China)
出处
《地球物理学进展》
CSCD
北大核心
2021年第3期1341-1348,共8页
Progress in Geophysics
基金
浙江省基础公益研究计划项目(LGF20D040001)
浙江省水利科技项目(RB1901)
浙江省省属科研院所扶持项目(ZIHEA20001)
浙江省水利河口研究院院长基金项目(岩土A19002)联合资助。
关键词
土石坝
渗漏诊断
并行电法
瞬变电磁法
联合探测
Embankment dam
Leakage detection
Parallel electrical method
Transient Electromagnetic Method(TEM)
Joint detection
