高庙子膨润土与砂混合物的土-水特征曲线

Soil-water characteristic curves of Gaomiaozi bentonite-sand mixtures

用滤纸法和压力板法对高庙子膨润土与福建砂的混合物进行试验研究,在不同孔隙比和不同膨润土与砂配合比情况下量测脱湿过程的土-水特征曲线,研究土-水特征曲线与孔隙比和配合比之间的关系。试验结果表明:在同一配合比下用饱和度与吸力表示土-水特征曲线时,其曲线随着孔隙比的减小向右上方移动,即当土样的吸力一定时,土样的饱和度随着孔隙比的减小而增大,当吸力小于10 MPa时,这种现象较为显著;在同一孔隙比下膨润土与砂混合物的土-水特征曲线随着膨润土的比例增加而向右上方移动,即混合物的进气值随着膨润土的比例增加而增大;另外,配合比以及孔隙比相同时,膨润土与福建砂的混合物的土-水特征曲线与日本产Kunigel膨润土与丰浦砂的混合物的土-水特征曲线非常接近。

The filter paper method and the pressure plate method are used for measuring the suction of Gaomiaozi bentonite-sand mixtures.The soil-water characteristic curves（SWCC） obtained during drying from the tests at different void ratios and different mixing ratios of Gaomiaozi bentonite to Fujian sand are compared.The effects of void ratio and the mixing ratio on SWCC are analyzed according to the test results.The results show that when the SWCC is expressed by the relation between suction and saturation degree,the SWCC moves up and right with the decreasing void ratio for a mixture with the same mixing ratio.That＇s to say,the saturation degree increases with the decreasing void ratio at a constant suction.Especially when the suction is less than 10 MPa,this phenomenon is evident;at constant void ratios,the SWCC moves up and right while increasing the mixing ratio.In other words,the value of air-entry suction increases with the increasing mixing ratio.In addition,when the mixing ratio and void ratio are the same,the SWCCs of Gaomiaozi bentonite-sand mixture and Kunigel bentonite-sand mixture are quite similar.