Mechanical Behavior of Frozen Soil Subjected to Freeze–Thaw Cycle Under Cyclic Impact Load and Passive Confining Pressure

Abstract

In this study, the effects of freeze–thaw cycles and cyclic impacts on frozen soil were systematically investigated. With an increase in the number of freeze–thaw cycles, the peak stress of frozen soil decreased until a stable state was achieved. Moreover, subjecting frozen soil to an increased number of cyclic impacts led to notable alterations in mechanical characteristics, including peak stress, critical strain and dynamic elasticity modulus. Both the freeze–thaw cycles and cyclic impacts were identified as primary damage mechanisms in understanding frozen soil degradation processes. Damage resulting from these impacts conformed to the Weibull distribution pattern. Damages induced by freeze–thaw cycles, individual impacts and cyclic impacts were integrated into the Zhu–Wang–Tang viscoelastic model (ZWT model). Relying on principles of elastic mechanics, the role of confining pressure on frozen soil was examined and subsequently integrated into an improved ZWT model. To evaluate the model’s effectiveness, its predictions were compared with experimental results.