某水库坝区渗漏原因分析

Cause Analysis of Dam Leakage of a Reservoir Project

某水库大坝为黏土心墙砂砾石坝,坝体采用黏土心墙防渗,坝基上部第四系松散堆积物采用混凝土连续墙防渗,下部基岩和两岸采用帷幕灌浆防渗。随着大坝填筑至坝顶,水库开始拦蓄少量河水,发现坝后排水棱体底部有多处渗水点,尤其是下游排水沟渗水明显。初步观测发现,各渗水点数量和流量有增多、增大发展趋势。坝区渗漏不仅影响水库效益,而且在坝体及坝基岩土体中可能发生渗透变形问题,危及大坝安全。通过对工程防渗体系勘察分析,初步查明了大坝渗漏原因及渗漏通道分布,为工程处理提供科学依据,确保水库安全运行。

The dam of a reservoir project a gravel dam with clay core.The dam body adopts clay core for seepage control.The upper Quaternary loose deposits of the dam foundation adopt concrete continuous wall for seepage control,and the lower bedrock and both banks adopt curtain grouting for seepage control.With the dam filling to the crest,the reservoir begin to retain a small amount of river water.It is found that there are many seepage points at the bottom of drainage prism behind the dam,especially in the downstream drainage ditch.The preliminary observation shows that the number and discharge of each seepage point are increasing and developing.The seepage in the dam area not only affects the reservoir benefit,but may cause seepage deformation in the dam body and the bedrock soil,endangering the dam safety.Based on the investigation and analysis of the anti-seepage system of the project,the causes of dam leakage and the distribution of leakage channels are preliminarily discovered,which can provide scientific basis for the project treatment and ensure safe operation of the reservoir.