3-D Finite Element Numerical Analysis Of Steel Sheet Pile Lattice Cofferdam And Research On Construction Methods

In recent years,with the development of social economy,people have never ignored environmental issues.As the improvement of environmental protection awareness,the traditional earth-rock cofferdam with greater impact on the ecological environment is gradually abandoned,people chosed a more economical and environmentally friendly cofferdam—steel sheet pile cofferdam.The steel sheet pile cofferdam has the advantages of fast construction speed,small construction site and teel sheet pile reusable.However,there are few application studies on the shape of steel sheet piles,and the calculation method is not yet mature.At present,most of the design methods are semi-empirical and semi-theoretical.This paper conducted research from the following aspects,and based on Changchun No.6 Water Purification Plant project construction.(1)Summarized the failure modes of steel sheet pile cofferdams,sort out the traditional calculation methods such as shear deformation calculation and overall stability calculation methods,and explore their application.(2)Explored the construction method of steel sheet pile lattice cofferdam,combined with engineering examples to chose the safest and most economical construction method,and selected three typical working conditional in the construction steps for subsequent numerical simulation.(3)Using ABAQUS software created numerical model of lattice steel sheet pile structure,selected the appropriate grid division scheme,and established a 3-D finite element rigid model for lattice steel sheet pile structure analysis.In the numerical model,the plastic deformation characteristics of the soil,the relative movement between the steel sheet pile and the soil are considered.(4)Using the established rigid model,combined with the water intake cofferdam project of Changchun No.6 Water Purification Plant,designed the structure.The circumferential stress of steel sheet piles and the distribution of earth pressure inside and outside the grid under different working conditions are analyzed to explore the mechanical characteristics and stability of the structure.