Study on Mathematical Stress-strain Model of Frozen-thawed Soil Based on Structure Mechanism

The stress-strain behavior of frozen-thawed soil is a main issue of the frozen soil mechanics. In this paper, the change rules of soft soil shear strength, friction angle, cohesive force and other mechanical parameters were studied. After frozen-thawed cycles, the friction angle of soft soil increases with lower cohesive force, the constitutive property gradually weakened with the nature of transformation from cohesive soil to cohesionless soil. Mathematical characteristics for shear stress-strain curve of frozen-thawed soil are analyzed. Structure mechanism index is presented to indicate the relation between stress-strain curve and soil structure mechanism. The result of this paper is helpful to the numerical analysis and practical engineering design of frozen-thawed soil foundations.