摘要
探地雷达和高密度电法等综合物探方法在水库大坝防渗体连续性和渗漏检测中的应用较多,由于探测深度受限,深峡谷区大坝部分防渗体连续性无法采用探地雷达检测。某心墙坝除险加固工程采用防渗墙和防渗帷幕处理后,渗流量变化不大。为进一步查明大坝渗漏原因,结合监测资料、压水试验、探地雷达、高密度电法及地勘资料对心墙坝防渗墙连续性和防渗帷幕防渗效果进行了研究。结果表明:防渗墙整体连续性较好,无明显缺陷,防渗墙局部存在不密实;下游侧坝体与左右岸坝肩均存在多处低阻异常区,在高程80.00~100.00 m之间坝体视电阻率值低于30Ω·m,坝体含水量偏高;监测资料表明防渗帷幕前后水头降幅较大,说明防渗帷幕的防渗效果良好,除险加固后大坝渗流量变化主要是降水入渗导致。监测资料、压水试验、探地雷达和高密度电法综合应用在深峡谷区心墙坝除险加固工程渗漏识别和防渗体防渗效果分析中具有较好效果,可为同类工程提供依据。
Due to the limited detection depth of ground penetrating radar(GPR), it cannot be used to detect the continuity of a part of the impervious body of the dam located within deep canyon area. After the anti-seepage treatment with cut-off wall and anti-seepage curtain being used for the risk-elimination and strengthening project of a core dam, the change of the seepage therein is not so large. In order to further find out the cause of the seepage from the dam, both the continuity of the cut-off wall and the anti-seepage effect from the anti-seepage curtain of the dam are studied in combination with the relevant monitoring data, water pressure test, GPR, high-density electrical method and geological exploration data. The result shows that the continuity of the cut-off wall is better without obvious defect, but the cut-off wall is locally not so dense and several low resistivity abnormal areas are there at both the downstream dam body and the dam abutments on the left and right banks, while the apparent resistivity of the dam body is lower than 30 Ω·m at the elevation of 80.00~100.00 m with higher water content inside the dam body. The monitoring data show that water head drop-amplitude before and after the anti-seepage curtain is larger, which indicates that the anti-seepage effect of the anti-seepage curtain is better and the change of the seepage after the risk-elimination and strengthening of the dam is mainly due to the rainfall infiltration. The integrated application of monitoring data, water pressure test, GPR and high-density electrical method has a better effect in the leakage identification for the risk-elimination and strengthening project of core dam located within deep canyon area, and then can provide a basis for the similar project concerned.
作者
方艺翔
李卓
范光亚
蒋景东
毕朝达
FANG Yixiang;LI Zhuo;FAN Guangya;JIANG Jingdong;BI Chaoda(Nanjing Hydraulic Research Institute,Nanjing 210029,Jiangsu,China;Dam Safety Management Center of the Ministry of Water Resources,Nanjing 210029,Jiangsu,China)
出处
《水利水电技术（中英文）》
北大核心
2022年第2期87-97,共11页
Water Resources and Hydropower Engineering
基金
国家自然科学基金项目(51979193)
国家重点研发计划项目(2018YFC0407105,2018YFC0407106)
中央级公益性科研院所基本科研业务费专项资金资助项目(Y721001)。
关键词
心墙坝
探地雷达
高密度电法
防渗墙
防渗帷幕
渗漏识别
core wall dam
ground penetrating radar
high-density electrical method
cut-off wall
anti-seepage curtain
leakage identification
