The Optimal Design Research And Numerical Simulation On Secant Pile For Deep Foundation

With the development of our economic, process of urbanization speed up,the scale and population of the cities are increasing,the demands of the convenient traffiction get more and more strong Because of the subway convenience punctuality and large capacity,it is noted by more and more people,more and more large cities began to plan or co nstruct subway project.however the scale of the subway foundation is very large, geological conditions of every cities are different from each other.All kinds of foundation pit support methods have been widely applied,secant pile is a emerging pit support method,because of its advantages,it is applied more and more extensively,but the research on the secant pile is not much.Firstly, the secant pile has not been applied widely, secondly, the structure of the secant pile is complicated, research is a little difficult.The first,in this paper, the reseach results and existing problems of the secant pile from home and abroad are introduced.Then, the paper set the station of qiutao road background,it research three aspects1. The secant pile is considered as usual bored pile in most foundation project, plain concrete pile is only considered its water sealing function, not being considered his load sharing function. however, by model testing and theoretical analysis, the plain concrete pile could bear certain load, the paper combined with specific ingeering example as qiutaoroad station, through the theoretical derivation,we can make optimization design on secant pile if considering the load shearing of plain pile.,though the reinforcement of the secant pile has been induced,it meet for carrying capacity demands completely.it has good economic effect.2. In order to comprehensive research the deformation rule of the secant pile and the rule of surface deformation,the paper collects data from a part of the foundation, making finite element caculation by using FLAC3D,analysising the deformation rule of the pile body and the the rule of surface deformation and the axial force of the support.3. Discusses the factors of affecting deep excavations as secant pile for the supporting structure, And it has got a variety of factors on the extent to the deformation by calculation and analysis, it provides valuable advice for the optimization at last.