Laboratory investigation on strength and deformation characteristics of ice-saturated frozen sandy soil

► Triaxial compression tests on an ice-saturated frozen sandy soil were carried out. ► The strength changing with confining pressure can be divided into three phases. ► A new strength criterion was proposed; the mechanism of strength was explained. ► An improved D-C model was applied to describe the stress-strain relationship. ► The reason why the model can describe strain-softening is explained.