Experimental study on the unloading characteristics of coarse aggregate under true triaxial shear loading#br#
WANG Yongxin1，SHAO Shengjun1，2，WANG Zhi1，LIU Aiguo1
(1. Institute of Geotechnical Engineering，Xi'an University of Technology，Xi'an，Shaanxi 710048，China；2. Shanxi Provincial Key Laboratory of Loess Mechanics and Engineering，Xi'an University of Technology，Xi'an，Shaanxi 710048，China)
Abstract：A series of loading and unloading tests under isotropic compression and shear were carried out by using the large true triaxial apparatus，the resilience characteristics of coarse-grained soils were described，and the value of the resilience modulus in different unloading stages was analyzed. The test results show that the resilience modulus changes greatly due to the influence of stress path in the shear process and cannot be replaced by the average resilience modulus. A prediction model which involves the spherical stress and the minor principal stress was obtained from a stress-dependent analysis and the Janbu model. When one of the variables is constant，the resilient modulus changes nonlinearly with the other variable and the function relationship is linear in the double logarithmic coordinate. Using the prediction model，the resilient shear modulus under different shear paths is obtained，and the regression parameters fit well in the model. The model reflects the influence of stress path and material response on the nonlinear resilience deformation characteristics and is conducive to a better understanding of the unloading characteristics of coarse-grained soils.
王永鑫1，邵生俊1，2，王 智1，刘爱国1. 真三轴剪切作用下粗粒料卸荷特性的研究[J]. 岩石力学与工程学报, 2020, 39(7): 1503-1512.
WANG Yongxin1，SHAO Shengjun1，2，WANG Zhi1，LIU Aiguo1. Experimental study on the unloading characteristics of coarse aggregate under true triaxial shear loading#br#. , 2020, 39(7): 1503-1512.
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2020, Vol. 39 
