某面板堆石坝异常渗漏综合勘察及分析评价

Comprehensive Investigation,Analysis and Evaluation on the Abnormal Seepage of a Concrete Face Rockfill Dam

某面板堆石坝建成蓄水后,导流洞及量水堰便出现了渗漏。渗漏量与库水位呈正相关,最大渗漏量合计为2 039.86 L/s。此外,渗水水温高于库水,二者温差最大达8.2℃。为查明渗漏特征、渗水来源及渗漏途径,采用了水文地质测绘、现场检查、钻探、物探、压水试验、水质全分析、长期观测、示踪试验、孔隙水压力及变形监测相结合的综合勘察方法。在此基础上,利用回归分析及地质比拟法对达正常蓄水位的渗漏量进行了预测。工程实践表明,针对渗漏采用多种手段相结合的勘察和分析方法是合理有效的。

After the reservoir is impounded, the diversion tunnel and measuring weir of a concrete face rockfill dam appears leakage. The seepage quantity has a positive correlation with reservoir water level and the maximum seepage quantity is 2 039.86 L/s. In addition, the temperature of seepage water is higher than that of the reservoir water and the maximum temperature difference is 8.2 ℃. In order to find out seepage characteristics, source and path, the comprehensive investigation methods of hydrogeological mapping, on-site inspection, drilling, geophysical prospecting, water pressure test, water quality analysis, long-term observation, tracer test, pore water pressure monitoring and deformation monitoring are adopted. On the basis of above analysis, the seepage quantity under normal water storage level is predicted by means of regression analysis and geological analogy. The engineering practice shows that the method of investigation and analysis combined with various means for seepage is reasonable and effective.