The nondestructive dynamical observations on the variation of density and moisture content of soil during freeze-thaw processes, the volumetric change, deformation and the development of cracks and structural defects of frozen soil samples subjected to stress, can be made using computer tomography (CT) technology. The mathematical model describing the changes of the physical and mechanical properties of frozen soil can be obtained by the analysis of these CT data. The nondestructive dynamical observations on the variation of density and moisture content of soil during freeze-thaw processes, the volumetric change, deformation and the development of cracks and structural defects of frozen soil samples subjected to stress, can be made using computer tomography (CT) technology. The mathematical model describing the changes of the physical and mechanical properties of frozen soil can be obtained by the analysis of these CT data.