土水特征曲线预测非饱和黏土的抗剪强度

doi:10.3969/j.issn.1007-2861.2015.01.015

Journal of Shanghai University（Natural Science Edition） ›› 2016, Vol. 22 ›› Issue (5): 648-655.doi: 10.3969/j.issn.1007-2861.2015.01.015

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Predicting shear strength of unsaturated clay using soil-water characteristic curve

LI Wanshuang, SUN Dean, GAO You

Department of Civil Engineering, Shanghai University, Shanghai 200072, China

Received:2015-01-29 Online:2016-10-31 Published:2016-10-31

Abstract

Abstract:

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.

Key words: filter paper method , shear strength, soil-water characteristic curve(SWCC) , pressure plate method

LI Wanshuang, SUN Dean, GAO You. Predicting shear strength of unsaturated clay using soil-water characteristic curve[J]. Journal of Shanghai University（Natural Science Edition）, 2016, 22(5): 648-655.

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Predicting shear strength of unsaturated clay using soil-water characteristic curve

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