为了研究穆棱季冻区粉质黏土的抗剪强度特性，通过构建含水率、冻结温度与融化时间的多变量耦合控制体系，系统开展了冻融循环剪切试验，得到穆棱季冻区粉质黏土在不同冻融条件下抗剪强度的变化规律。结果表明：穆棱季冻区土体抗剪强度受含水率、融化时间与冻结温度的影响较大，当含水率大于最优含水率时，冻结时抗剪强度随着含水率的增高而增大，随着融化时间的增长，试样的抗剪强度随着含水率的升高而降低，当土体含水率在最优含水率附近时，抗剪强度受含水率升高的影响不明显；土体处于冻结状态时，抗剪强度变化率随冻结温度的降低而增大，随着融化时间的增长，冻结温度对试样抗剪强度变化率的影响逐渐减小；试样从冻结状态至融化6 h，抗剪强度变化率发生显著的降低，当完全融化后，试样抗剪强度变化率基本稳定在0.8附近。研究成果提升了季冻土抗剪强度随冻融条件而变化的规律认识，为冻融过程中抗剪强度参数设计提供了冰水相变动态机制的相关理论依据。

In order to study the shear strength characteristics of silty clay in the seasonally frozen area of Muling, cyclic freeze-thaw shear tests were systematically conducted through establishing a multivariable coupled control system incorporating water content, freezing temperature, and thawing duration. The variation patterns of shear strength in Muleng silty clay under different freeze-thaw conditions were obtained. The results show that the shear strength of the soil in the seasonally frozen area of Muling is significantly affected by water content, thawing time and freezing temperature. When the water content is greater than the optimum water content, the shear strength during freezing increases with the increase of the water content. As the thawing time increases, the shear strength of the specimens decreases with the increase of the water content. When the water content of the soil is close to the optimum water content, the influence of the increase in water content on the shear strength is not obvious. When the soil is in the frozen state, the change rate of the shear strength increases with the decrease of the freezing temperature. With the increase of the thawing time, the influence of the freezing temperature on the change rate of the shear strength of the specimens gradually decreases. From the frozen state to 6 hours of thawing, the change rate of the shear strength decreases significantly. When completely thawed, the change rate of the shear strength of the specimens is basically stabilized around 0.8. The research findings enhance the mechanistic understanding of shear strength evolution in seasonally frozen soils under cyclic freeze-thaw conditions, providing theoretical foundations related to the dynamic mechanisms of ice-water phase transitions for the design of shear strength parameters during freeze-thaw processes.