非饱和膨润土掺砂混合物的水力和力学性质  

Hydraulic and Mechanical Behavior of Unsaturated Sand-Bentonite Mixture

作　　者：孙德安[1] 闫威[1] 孙文静[1] 

机构地区：[1]上海大学土木工程系,上海200072

出　　处：《上海大学学报（自然科学版）》2010年第2期196-202,共7页Journal of Shanghai University:Natural Science Edition

基　　金：上海浦江人才计划资助项目(06DJ14043);国家自然科学基金资助项目(10972130)

摘　　要：采用压力板法和滤纸法对膨润土掺砂混合物土-水特征曲线的低吸力段(<1.5 MPa)与高吸力段(>1.5MPa)分别进行量测.不同吸力测试方法得到的试验结果具有较好的一致性.根据试验测得的土-水特征曲线,得到混合物的残余含水量和进水值;利用吸力可控制的非饱和土固结仪,进行不同常吸力下膨润土掺砂混合物的压缩试验,得到不同吸力下的压缩曲线.试验结果表明:随着施加吸力的增大,膨润土掺砂混合物的屈服应力增大,而压缩指数减小;同一吸力下,湿化段上吸力对应试样的屈服应力大于经过湿化饱和后处于干化段上吸力对应试样的屈服应力.This paper presents test results carried out on heavily compact sand-bentonite mixtures. To measure suction of the mixture in a larger range of water content, a pressure plate apparatus and filter papers are used. The obtained soil-water characteristic curves shows that the results obtained from the two methods are consistent. The residual water content and water entry value are determined from the measured curve. By using a suction-controllable oedometer for unsaturated soil, a series of onedimensional compression tests were performed on unsaturated compacted sand-bentonite mixtures with different constant suctions. The test results indicate that the yield stress increases and compression index decreases with increase of the imposed suction.

关 键 词：膨润土掺砂混合物 缓冲/回填材料 土-水特征曲线 压缩曲线 

分 类 号：TU443[建筑科学—岩土工程]