含大尺寸块石岩土材料土水特征曲线的试验

利用压力板法对乐昌峡坝肩边坡岩土材料的土水特性进行了室内试验研究,测量并分析了含大尺寸块石的强风化岩层的土水特征曲线.首先,对于含大尺寸块石的强风化岩层,本试验依据颗粒级配配比原料,按照一定的干密度制备试样,测量了强风化重塑试样的土水特征曲线,比较了左、右岸强风化岩层的土水特性;其次,测量了全风化原状土和重塑土的土水特征曲线,对比分析了强风化岩层与全风化岩层的土水特性差异,总结了含大尺寸块石强风化材料土水特性的特点,并就试验合理性展开相关讨论;最后,拟合了各种材料的土水特征曲线,得到相关表征各材料土水特性的参数.试验研究表明:影响含大尺寸块石岩土材料土水特性的因素中,颗粒级配的影响明显强于矿物成分的影响;与全风化土质材料相比,含大尺寸块石强风化岩层试样含水量较低,残余含水率偏小,持水能力较弱,且相对于全风化岩层原状试样和重塑试样,强风化岩层重塑试样的土水特性更接近于全风化岩层重塑试样.该试验对含大尺寸块石岩土材料土水特性的试验研究进行了初步探索,试验结果对乐昌峡工程具有一定的指导意义.

Experiment on SWCC of rock and soil materials with large stones

Through the method of pressure board,soil-water characteristic of rock and soil materials of Lechang Gorge were researched,soil water characteristic curve(SWCC) of highly weathered materials with large stones were analyzed.Firstly,SWCC of highly weathered disturbed materials were measured,samples were made based on particle grade and dry density,soil-water characteristic of highly weathered materials between left and right abutments of Lechang Gorge were compared;Then,SWCC of fully weathered original and remolded materials were measured;soil-water characteristics between highly weathered and fully weathered materials were compared;some characteristics were summarized;and their rationalities were discussed.Finally,through fitting parameters of SWCC of each material,some soil-water characteristic indicators were obtained.Experiment results indicate: For the SWCC of highly weathered materials with large stones,the influence of particle grade is stronger than material composition.Compared with fully weathered materials,the highly weathered materials with large stones possess lower water content,smaller residual water content and weaker water holding capacity.And compared with fully weathered original and remolded materials,the soil-water characteristic of highly weathered remolded materials is similar to fully weathered remolded materials.This experiment took a tentative step on the study of SWCC of highly weathered materials with large stones.The experiment results are also useful for guiding the construction of Lechang Gorge engineering.