| In this thesis, the theory of artificial freezing method and the condition of research and application at home and abroad are presented. This thesis introduces the artificial frozen earth's mechanics parameters and property. The principle and method of designing elaborated on the frozen soil wall and the freezing parameters are stated. The emphasis of the thesis is the designing proposal of the freezing method by the case of a subway of Guangzhou. In the thesis, the thickness of ice-wall is preliminarily calculated using analytic and empirical equations separately. Adopting the thickness gained above, the temperature fields of the ice-wall and soil around, built with different quantities and distribution forms of freeze-tubes, are analysed by ANSYS. Meanwhile, the process of active freezing has been over-all simulated, so as to determine a proper quantity and distribution form of freeze-tubes, as well as the active freezing period, which can be used for guiding the construction. Besides these above, an empirical equation for freezing period calculation is adopted; and the result is compared with that gained from numerical simulation, so the active freezing period is ultimately determined. Then numerical simulation software ANSYS is applied to simulate the excavating process, and stability analysis on ice-wall is conducted, then the design thickness of the ice-wall is finally determined. The project is successful in safety and social efficiency. That experience can be referred to by other similar constructions.
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