IMPACT OF SOIL FROST HEAVE ON PILE SUPPORTING STRUCTURE

With the development of the city, more and more projects go to the ground, to the underground space. There are more and more foundation pit projects, foundation pit engineering accidents also gradually appear. China's permafrost and seasonal frozen soil area is respectively 21.5% and 53.5% of the total land area. In theseareas, building foundation pits often damage by freezing and thawing cycle, causing great security hidden danger for foundation pit retaining structure safety in cold areas, putting forward a lot of new challenges to the research, design and construction units. Article based on the finite difference analysis software FLAC3D, using the flexibility of numerical simulation method, selecting of appropriate constitutive model, simulate the frost heave on the foundation pit.it is concluded that foundation pit temperature field variation law, law of supporting pile top displacement change with temperature, and puts forward several measures to reduce the displacement of pile body frost heave, to provide reference for design and construction of foundation pit supporting pile wintering in the future.