Experimental Study on Triaxial Mechanical Properties of High−Temperature Frozen Loess under Different Moisture Content and Confining Pressure in Yili, Xinjiang

In order to explore the influence of moisture content and confining pressure on the physical and mechanical properties of high−temperature frozen loess, taking the loess as the research object in Yili valley, Xinjiang. The mineral composition and physical properties of loess, as well as the triaxial compression tests under different moisture content and confining pressure were carried out. The results show that the content of silt and clay is high in Yili loess, which is sensitive to freezing−thawing. At low water content, the failure mode is strain softening and brittle shear failure, while at saturated water content, the failure mode is strain hardening and plastic bulging deformation failure. The softening coefficient decreases gradually with water content increasing. With the increase of water content, the peak residual friction angle gradually decreases, the peak residual cohesion gradually increases, and the deformation modulus increases. With the increase of confining pressure, the elastic modulus and characteristic parameters of damage evolution gradually decrease, and the damage mechanics constitutive model introduced can better describe the whole process of stress and strain of high−temperature frozen loess under different water content and confining pressure. The research results can provide mechanical parameters and theoretical basis for the study of mechanism of freeze−thaw landslide in Yili Valley.