Abstract: As a common type of geotechnical material, the heavily weathered basalt has its unique mechanical properties in the frozen state, which has an important influence on engineering design and construction. However, there is relatively few research on the mechanical properties of heavily weathered basalt in the frozen state. In this paper, the influence of water content, confining pressure and freeze-thaw cycles on the mechanical properties of the heavily weathered basalt under freezing conditions is studied. Triaxial shear experiments are carried out on the heavily weathered basalt under freezing conditions with water content, confining pressure and freeze-thaw cycles as control variables to evaluate the changes of stress-strain curve and strength and to analyze their influence on mechanical properties. The results show that the mechanical properties of the heavily weathered basalt under the freezing condition are affected by the initial water content, the confining pressure and the freeze-thaw cycles. Based on the analysis of its strength and stability changes, the mechanical properties of the heavily weathered basalt under the freezing state and provides mechanical parameters and theoretical basis for its engineering design and construction.

Key words: Frozen Soil, Mechanical Property, Triaxial Shear, Highly Weathered Basalt