Attenuation Law of Shear Strength Between Residual Soil and Freeze-thaw Interface Under Short-term Frost Climate

Short-time freeze-thaw has certain effects on the stability of shallow slopes, in order to reveal the attenuation law of shear strength between residual soil and freeze-thaw interface under short-term freeze-thaw cycles, direct shear tests were carried out under different freeze-thaw conditions. The results show that damage degree of the shear strength parameters of residual soil is larger than that of freeze-thaw interface, and it decreases exponentially with the increase of freezing-thawing times. The main damage occurs during the first 3 times. When the moisture content is 21.5%. The cohesion damages of residual soil and freeze-thaw interface are 41% and 22% respectively, while the internal friction angle damages are 14% and 10%. The influence of freeze-thaw cycles on strength and strength parameters between residual soil and freeze-thaw interface increases with the increase of moisture content, cycles and cold end temperature. The freeze-thaw damage model of shear strength parameters was established and verified.