深厚覆盖层拦河闸坝基础特性分析及处理研究

Characteristic Analysis and Treatment Study on Gate Dam Foundation on Deep and Thick Overburden

某水电站坝址区河床覆盖层深厚,厚度在80~133 m之间,河床覆盖层成分、成因及结构复杂,各层物理力学性相差性较大。勘探和试验资料表明,河床覆盖层基础承载力低、渗透性强,基础处理难度大。文章介绍了闸址覆盖层工程地质条件、特性,针对覆盖层特性,开展了基础加固处理、基础防渗处理、砂层抗液化处理研究,该工程基础处理思路可为其它工程提供参考。

The riverbed overburden in dam site area of a hydropower project is deep and thick. Its thickness is 80 - 133 m. The overburden components, formation causes and structure are complicated. The physical mechanics of layers are quite different. The exploration and test data demonstrate that the bearing capacity of the riverbed overburden foundation is lower, its permeability is strong and its foundation treatment is difficult. In the paper, the engineering geological conditions and characteristics of the overburden in the dam site area are introduced. In consideration of the overburden characteristics, the foundation reinforcing treatment, impervious handling and sand liquefaction treatment are studied. The foundation treatment concept provides other projects with reference.