Experimental study of the failure function of frozen clay in the π-plane [π平面上冻结黏土破坏函数适用性试验研究]

作者：Chen D.; Ma W.; Mu Y.^*; Zhou Z.; Wang D.; Lei L.

来源：Journal of China University of Mining & Technology, 2019, 48(1): 64-70.

• Hollow cylinder testing system
• Ratio of failure stress
• Strength of frozen soil
• Stress Lode angle
• Π-plane

To study the strength properties of frozen soil in the π-plane, a series of directional shear tests were carried out on frozen clay under five stress Lode angles (θσ=-30.0°, -16.1°, 0°, 16.1°, and 30.0°) and four mean principal stresses (p=1.0, 3.0, 4.5, and 10.0 MPa) at -6.0 ℃. The results show that the stress-strain behavior of frozen clay performs as strain hardening under directional shearing. With the coefficients of intermediate principal stress (b-value) increases, the axial strength decreases gradually. With the increase of the mean principal stress (p-value), the influence of the b-value on the curve of generalized shear stress-strain weakens. The influence of the b-value on the ratio of failure stress is greater when p-value is small and vice versa. The ratio of failure stress decreases with the p-value increase under the same b-value. In the π-plane, the failure curve of frozen clay changes from a curve-sided triangle to a circle. Simulation of the test results in this study shows that the generalized nonlinear strength theory (GNST) can describe this evaluation rule better than others.

• 单位
  中国科学院; 中国科学院大学