Effects of pore solution concentrations on shear strength of clay
YU Hai-hao1, 2, WEI Chang-fu1, 2, YAN Rong-tao1, 2, FU Xin-hui3, MA Tian-tian4
1. Guangxi Key Laboratory of New Energy and Building Energy Saving, Guilin 541004, China; 2. College of Civil Engineering and Architecture, Guilin University of Technology, Guilin 541004, China; 3. Fujian Provincial Institute of Architectural Design and Research, Fuzhou 350001, China; 4. State Key Laboratory of Geomechanics and Geotechnical Engineering, Institute of Rock and Soil Mechanics, Chinese Academy of Sciences, Wuhan 430071, China
Abstract：Pore solutions play an important role in the shear strength of soils. A series of shearing and microcosmic tests are performed on the samples saturated with NaCl solutions with different concentrations to investigate the effects of pore solution concentrations on the effective strength of clay. The experimental results show that the pore solution concentrations have strong effects on cohesion of samples. The cohesion decreases with the increase of pore solution concentrations. As the concentration approaches 0.1 mol/L, the cohesion decreases to below 0 kPa. The cohesion depends on the block effect of physical and chemical forces between particles on the interparticle sliding. The repulsion decreases with the increase of the pore solution concentration which makes the interparticle sliding more easily. Due to the development of real pore pressure in the samples, the cohesion decreases to below 0 kPa. The environmental scanning electron microscopy tests on the microstructures confirm that clays form flocculation in NaCl solution and form aggregation in water.
于海浩, 韦昌富, 颜荣涛, 傅鑫晖, 马田田. 孔隙溶液浓度的变化对黏土强度的影响[J]. 岩土工程学报, 2015, 37(3): 564-569.
YU Hai-hao, WEI Chang-fu, YAN Rong-tao, FU Xin-hui, MA Tian-tian. Effects of pore solution concentrations on shear strength of clay. Chinese J. Geot. Eng., 2015, 37(3): 564-569.
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