某水库右坝段坝基渗漏特征及原因分析

针对中小型水库中的土石坝容易出现坝基、坝肩和绕坝渗漏的问题,分析了某水库右坝段渗漏部位及由此导致水库无法蓄水的具体原因。通过分析坝址区水位监测孔、钻孔取芯、压水试验、波速测井和钻孔全景成像等资料,发现该水库无法蓄水的最主要原因是坝基灌浆帷幕效果(透水率小于3Lu)未达到预期效果,基岩顶板渗透率很大,仍是主要的渗漏部位和通道,主要渗漏范围为灌浆盖板以下10m内,缘于未探明F3断层和三条张开度极大的卸荷裂隙情况,致使防渗处理存在缺陷。右岸山体基岩裂隙水的地下赋存与冻融对坝后渗漏通道的形成有一定促进作用,应该做出相应风险和灾害评估。研究成果可为类似工程提供参考。

Analysis of Seepage Characteristics and Causes of Dam Foundation of the Right Dam of A Reservoir

In recent years, the soil dam for small and medium-sized reservoirs was prone to appear leakage in dam foundation, abutment and dam. In this paper, the leakage of the right dam section of a reservoir was studied and the specific reasons for the impossibility of reservoir storage were analyzed. Through the analysis of the data obtained from the water level monitoring hole, borehole core, water pressure test, wave velocity logging and borehole panoramic imaging of the dam site, the main reason why the reservoir can not be successfully stored is that the dam foundation grouting curtain effect did not achieve the desired effect (water permeability less than 3 Lu). The bedrock roof permeability is still large, and it is the main leakage sites and channels. The main leakage range is below the grouting cover 10 m. The F3 fault and three open great unloading fissures are not carried out to a deeper level of proof and seepage treatment, leaving it as a potential leakage channel. In addition, the underground occurrence and freezing and thawing of the fissure water of the right bank of the right bank have a certain effect on the formation of the leakage channel, and the corresponding risk and disaster assessment should be made. Research results can be used as reference for the similar projects.