Definition of failure criterion for frozen soil underdirectional shear-stress path

作者：Dun Chen,Wei Ma,GuoYu Li,ZhiWei Zhou,YanHu Mu,ShiJie Chen

摘要：A series of directional shear tests on remolded frozen soil was carried out at 10°C by using a hollow cylinder apparatus to study failure criterion under a directional shear-stress path.Directional shear tests were conducted at five shear rates(10,20,30,40,and 50 kPa/min)and five intermediate principal stress coefficients(b=0,0.25,0.5,0.75,and 1),with the mean principal stress(p=4.5 MPa)kept constant.The results show that the torsional strength and the generalized strength both increase with the increase of the shear rates.According to the failure modes of frozen soil under different shear rates,the specimens present obvious plastic failure and shear band;and the torsional shear component dominates the failure modes of hollow cylindrical specimens.A shear rate of 30 kPa/min is chosen as the loading rate in the directional shear tests of frozen soil.The shape of the failure curve in theπplane is dependent on the directional anglesαof the major prin cipal stress.It is reasonable to use the strain-hardening curves to define the deviatoric stress value atγg=15%(generalized shear strain)as the failure criterion of frozen soil under a directional shear-stress path.

发文机构：State Key Laboratory of Frozen Soils Engineering State Key Laboratory for GeoMechanics and Deep Underground Engineering Da Xing'anling Observation and Research Station of Frozen-Ground Engineering and Environment

关键词：FROZENsoilHOLLOWCYLINDERapparatusINTERMEDIATEprincipalstresscoefficientfailureCRITERIONdirectional

分类号： O34[理学—固体力学][理学—力学]