Experimental study on non-coaxiality and influence factors of intact Hangzhou soft clay
YAN Jia-jia1, ZHOU Jian1, GUAN Lin-bo2, GONG Xiao-nan1
1. Research Center of Coastal and Urban Geotechnical Engineering, Hanzhou University, Hangzhou 310058, China; 2. Zhejiang College of Tongji University, Jiaxing 314051, China
Abstract：The Saint Venant’s postulate is inapplicable to soil materials, namely there is a deviation between the major principal stress and strain increment directions. A series of tests with principal stress rotation are carried out on intact Hangzhou soft clay with ZJU-HCA. The stress paths under continuous rotation, cyclic rotation of principal stress and increasing principal stress direction angle and deviatoric stress are designed to study the non-coaxiality behaviors and influence factors. The non-coaxiality between the principal stress and strain increment directions is remarkable and quite different from that of sands. The degree of non-coaxiality in the tests with larger deviatoric stress or principal stress rotation with increasing deviatoric stress is smaller. In the cyclic principal stress rotation tests, the non-coaxiality is more complex when b≠0. The non-coaxiality is more significant when the samples experience reverse rotation of the principal stress. Additionally, the degree of non-coaxiality decreases as the development of shear strain and sometimes even negative values is investigated in non-coaxial angle.
严佳佳, 周建, 管林波, 龚晓南. 杭州原状软黏土非共轴特性与其影响因素试验研究[J]. 岩土工程学报, 2013, 35(1): 96-102.
YAN Jia-jia, ZHOU Jian, GUAN Lin-bo, GONG Xiao-nan. Experimental study on non-coaxiality and influence factors of intact Hangzhou soft clay. Chinese J. Geot. Eng., 2013, 35(1): 96-102.
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