掺砾风化料作为高坝心墙防渗体的试验研究

Experiment and Study on Gravel Weathered Material as Impervious Body for Core Wall of High Dam

结合糯扎渡水电站260 m级高坝心墙防渗料采用风化料及掺砾风化料的现场碾压试验,进行了现场渗透及现场大型直剪试验研究,风化料及掺砾风化料的室内外试验垂直渗透系数和水平渗透系数均小于i×10-5cm/s,两种料的渗透性均满足工程要求。风化料经掺砾后,其抗剪强度得到良好改善,有利于降低高坝建成蓄水后心墙的变形量,使之与堆石的变形协调。

The in-situ seepage test and in-situ large direct shear test are made combining with the in-situ rolling test for the core wall of 260 m high dam in Nuozhadu Hydropower Station, the impervious material of which is weathered material or gravel weathered material. The vertical permeability coefficient and horizontal permeability coefficient of the weathered material and gravel weathered material from indoor and outdoor tests are all less than 1×10^-5cm/s, and the permeability of all the two materials meets the needs for the engineering. After admixing with the gravel, the strength of the weathered material is improved favorably to reduce the deformation of the core wall after water storage of the high dam, so as to coordinate into the rockfill.