土工膜堆石坝, 渗漏异常, 渗漏通道, 渗透稳定性

A large amount of leakage occurred in a geomembrane rockfill dam after impoundment. After five treatments, the leakage still reached 632 L/s, relatively large among similar projects. The geophysical detection, underwater inspection and monitoring data are combined to analyze the possible leakage passages. The results show that there may be leakage passages in the anti-seepage curtain of lower grouting adit on the right bank of dam. The calculation results of the seepage stability of dam foundation show that some local seepage gradient in dam foundation is larger than the allowable seepage gradient. As safety hazards exist in the long-term dam operation, corresponding engineering measures should be taken to guarantee safe operation.

geomembrane rockfill dam, abnormal leakage, leakage passage, seepage stability