Analysis Of The Thermal Field Around The Tower Foundation In Permafrost Region

Frozen soil is a kind of extremely unsteady soil which is sensitive to the change of climate and environment. In permafrost areas, temperature field redistributes under the influence of climate change and human behavior. It can cause severe deformation and collapse of tower foundation in permafrost areas. Therefore, temperature field is taken increasingly seriously because it determinates tower foundation’s capacity.In recent years, with the rapid development of the transmission line, bearing load is increasing more. The traditional digging foundation and shallow buried foundation are difficult to meet the demands. Bored pile is commonly used in engineering construction in permafrost areas, because of its high bearing capacity, wide application and easy construction method. However, the shortcoming is that it affects permafrost a lot and takes long to refreeze. The main source of thermal disturbance is the heat of concrete hydration.In this paper, according to the theory of heat transfer and hydration heat of concrete, finite element software COMSOL Multiphysics is used to simulate the temperature field and refreezing process by given differential control equations and boundary conditions under different molding temperature and heat hydration. The changing rule of temperature of soil around pile with time and depth can be exactly obtained, considering shape of foundation and climate change. Some main results are obtained which are significant for constructions in permafrost areas theoretically and practically.