| This thesis put up the freezing-thawing mechanics of soft rock basing on the frozen soil which has developed. The problems involved and proposed problems need to solve have all pointed out. With the development in the west of China, the cold regions engineering become more important, especially the engineering geology and geotechnical engineering problem, which freezing-thawing environment affect the stability of cold region soft rock mass structure. Because the soft rock possess the special weak, high void ratio, expensive mineral and loose characteristics, it is not easy to master clearly the process of soft rock freezing-thawing. During the process of freezing and thawing , moisture and heat will transfer greatly ,which impart the stress distribution in the soft rock mass, so that cause the engineering structure to failure. In cold region , frozen heaven force is the main factor to the stability of engineering. This thesis base on the analysis of the physics properties of soft rock and the water-rock interaction ,according to the continuum medium theory, heat conduct and mass transfer theory, the basic equation was set up ,taking into account the main processes during soft rock freezing-thawing, including rock water movement, heat conduct, phase change of water and relevant latent heat. With the application of FEM software ANSYS, simulating the temperature field distribution of soft rock tunnel and the coupled simulation of temperature-stress field. The result is accorded with the practice.Regarding the soft rock as space elasticity mass, we set up the moisture-heat-stress coupling models, meantime, the damage of the mechanical properties should also be taken into account. Through analytical method to work out the value of frost heaving force, utilizing the equation of rheologial damage to determine the soft rock damage parameter and elastic modulus in the different stage . This is a new topic, it will supply a valuable reference in practical engineering study. ...
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