收稿日期: 2015-01-29
网络出版日期: 2016-10-31
基金资助
国家自然科学基金资助项目(11272194)
Predicting shear strength of unsaturated clay using soil-water characteristic curve
Received date: 2015-01-29
Online published: 2016-10-31
李万双, 孙德安, 高游 . 土水特征曲线预测非饱和黏土的抗剪强度[J]. 上海大学学报(自然科学版), 2016 , 22(5) : 648 -655 . DOI: 10.3969/j.issn.1007-2861.2015.01.015
The pressure plate method and filter paper method were used to measure the soil-water characteristic curve (SWCC) of clay with almost the same initial void ratio. Shear strength were obtained by performing a series of direct shear tests on the clay under different unsaturated conditions. SWCCs of the silty clay obtained with the pressure plate and filter paper methods were nearly the same. With the same pressure, shear strength increased with a decreasing degree of saturation, and decreases at a very low degree of saturation. The degree of saturation had great influence on cohesion and little influence on the internal friction angle. Shear strength of unsaturated clay was predicted using SWCC. To precisely predict shear strength, a concept of effective degree of saturation was introduced to modify the traditional strength formula of unsaturated clay. The modified formula could better predict tested data.
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