Effects of shear rate on strength properties and pile-soil interface of marine soft clay
KONG Ling-wei1, XIONG Chun-fa1, 2, GUO Ai-guo1, YANG Ai-wu1, 3
1. State Key Laboratory of Geomechanics and Geotechnical Engineering,Institute of Rock and Soil Mechanics,Chinese Academy of Sciences, Wuhan, Hubei 430071 China; 2. Guangxi Key Laboratory of Road Structure and Materials, Guangxi Transportation Research Institute, Nanning, Guangxi, 530007 China; 3. Key Laboratory of Soft Soil Characteristics and Engineering Environment of Tianjin, Tianjin Chenjian University, Tianjin 300384, China
Abstract：The CU triaxial tests and ring shear tests on interface between steel pipe pile and soil of a kind of intact marine soft clay with medium structure are carried out under influence of shear strain rate, and the variations of strength properties and pile-soil interface properties of the tested soil with shear strain rate are analyzed. Moreover, simulation tests on the reconsolidated soft clay around the pile after shearing are also conducted to analyze the strength behaviors of pile-soil interface. The results show that the shear strength and internal friction angle of the tested soil increase with the increasing shear strain rate monotonously, while the variation characteristics of the cohesion are opposite. Under the undrained condition, it is also found that the peak shear strength and internal friction angle of the pile-soil interface increase with the increasing shear strain rate, and the strain softening phenomenon becomes more obvious, however, the corresponding variations of residual shear strength and internal friction angle are very small. Although the peak shear strength of reconsolidated soil around the pile after large shear deformation tends to decrease, the residual shear strength increases, which shows the strength recovery characteristics of pile-soil interface.
孔令伟, 熊春发, 郭爱国, 杨爱武. 海积软黏土的强度特性与桩土界面剪切速率效应[J]. 岩土工程学报, 2017, 39(z2): 13-16.
KONG Ling-wei, XIONG Chun-fa, GUO Ai-guo, YANG Ai-wu. Effects of shear rate on strength properties and pile-soil interface of marine soft clay. Chinese J. Geot. Eng., 2017, 39(z2): 13-16.
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