Analysis Of Refrozen Of Bored Pile In Permafrost Region

China is a country with large permafrost. The structures which are constructed in permafrost region are influenced by the instability of frozen soil on thermodynamics. It is universal that the structures are destroyed in permafrost region for the frost heave and it is serious influenced the normal traffic of our country. It is important for people to study frost heave of frozen soil. There are no more perfectly system of theory for the study of frost heave. People usually study the frost heave by doing experiment during the real engineering. The thesis mainly study course of freezing soil when the bored pile has cast the concrete, that is, studying the temperature file between frozen soil and bored pile. In the thesis, firstly, the author introduces the actuality and the development of study frost heave of our country and oversea. Secondly, the author sum up forms of piles in the permafrost, characteristic of frozen soil in engineering, property of mechanics and the way of calculate temperature of frozen soil. The author also introduces some basic theory of frost heave and frost heave force and then introduces basic functions of ANSYS in thermal model. In the thesis, the author uses for reference the way which people use to study the problem between soil and pile, uses for reference the basic theory of thermodynamics during the study. The author also consider the special character of frozen soil, for example, enthalpy of frozen soil and consider the effect of hydrate of concrete after casting the concrete, building the finite element model of different length and radius of pile and different temperature of casting concrete by ANSYS software in thermal model, finding out distributing of temperature field between the permafrost and bored pile on the condition of considering factor of time(transient). The result of finite element model created by ANSYS is verified by the single pile experiment in KunLunShan permafrost zone , lately. On the basis of the finite element model, this thesis mainly consummate four aspects of works following. Firstly, the author analyses the effect of bored pile during refrozen by different length of pile and find out different curve of temperature of bored pile. Secondly, the author analyses the effect of bored pile during refrozen by different radius of pile and find out different curve of temperature of bored pile Thirdly, the author analyses the effect of bored pile during refrozen by different temperature of casting concrete and find out different curve of temperature of bored pile. Lately, the function of hydration of concrete is reduced with the distance from pile increasing. The author find out the incidence which hydration of concrete effect on permafrost on the bases of the result of finite element model that created by ANSYS.