Damage properties and influence factors of remolded frozen clay

Abstract: Based on the theories of the continuum damage mechanics and the methods for transversely isotropic damage variables, the damage properties of remolded frozen clay are systematically analyzed under different temperatures, moisture contents and confining pressures by using the conventional triaxial shear tests. The research results show that: (1) the damage evolution behaviors of the remolded frozen clay under different test conditions are consistent, that is, the early stage has rapid growth and the later stage has gentle change and the maximum interaxial damage variable D_1max generally ranges from 0.6 to 0.8; (2) the freezing temperature has obvious effect on the damage properties of the remolded frozen clay, and lowering the temperature may strengthen the structure obviously so as to reduce its structural damage and to delay its damage evolution; and (3) the secant modulus can well represent the development characteristics of cracks and the damage evolution behaviors of the remolded frozen clay during the loading procedure, and the relationship between the axial strain and the secant modulus of the damage threshold and temperature rises linearly, the damage strain threshold generally ranges from 0.3% to 0.7% and the corresponding secant moduli generally range from 200 MPa to 550 MPa.