Deformation failure and energy properties for frozen soils with thermal gradients

A series of triaxial compression tests on frozen clay are conducted under various thermal gradients and consolidation pressures by means of the K₀DCGF (K₀ consolidation, freezing with non-uniform temperature under loading) method. The deformation failure characteristics and compression energy are investigated. The test results indicate that the frozen saturated clay with thermal gradients has brittle characteristics. However, the frozen saturated clay with uniform temperature presents the plastic characteristics. The deformation process for frozen clay with thermal gradients can be divided into three stages elastic deformation stage, micro-fissures (or micro-holes) developing stage before the axial stress reaches the peak value and the micro-fissures transfixion stage when the axial stress is greater than the peak value. The ratio of the elastic strain energy to the total input energy increases with the increase of the thermal gradients and consolidation pressures. This phenomenon is correspondent to the relationship between the brittle characteristics and the thermal gradients and consolidation pressures.