两河口水电站心墙防渗料掺砾试验

为改善作为心墙防渗料的含砾低液限黏土的强度和变形性质,对两河口水电站300 m级心墙堆石坝防渗料进行掺砾研究,分别进行了击实试验和力学性质试验。试验结果表明:随着掺砾比增大,心墙防渗料的最大干密度逐渐增大,最优含水率逐渐减小;掺砾比为40%的心墙防渗料的变形和强度性质较好,临界水力梯度最高;掺砾比为30%和40%的心墙防渗料的渗透系数更接近规范要求。推荐两河口水电站心墙堆石坝心墙防渗料的掺砾比为40%。

An experimental study of gravelly impervious materials for core wall in Lianghekou Hydropower Station

In order to improve the strength and the deformation properties of gravelly low liquid-limit clay as impervious material for a core wall,compaction and mechanical tests were conducted for the clay of the core rockfill dam(300m in height) at Lianghekou Hydropower Station.The experimental results show that the maximum dry density of mixed materials increases and its optimum moisture content decreases with the increase of gravel content;the strength and the deformation properties of mixed material with 40% gravel is the best and its critical hydraulic gradient is the highest;and the permeability coefficient of the impervious soil with 30% and 40% gravel is closer to the standard requirement.Therefore,the suggested gravel ratio of the impervious soil materials for Lianghekou Hydropower Station is 40%.