The Optimization Study Of The Pile Spacing For The Bridge Pile Foundation

In the design of pile foundation, it's an important problem to adjust the pile spacing to make the displacement and the stress of the pile group foundation and the money used in the engineer reasonably. Technical code for design of building foundation and technical code for building pile foundation prescribe the minimum pile spacing of every kind of piles, which ensure that the designed pile spacing is close to the pile spacing of the maximum effect for pile group in order to get a higher effect for pile group. After deciding the number of the pile foundation and the minimum pile spacing, the pile cap of the single foundation commonly obtains a least dimension of the cap to design the pile foundation. Because the increased dimension of the cap will be lead to the increased material wastage. So it's meaningfully to minish the pile spacing reasonably within the safety limit.Firstly, the article summarizes the research development in and out of China. The work done in this thesis mainly included:(1)The information and scheme of finite element has been established. Performance of a single pile and pile group foundation is simulated by ANSYS FEM (Finite Element Method) program.(2)By analyzing the calculated results, it's possible to minish the pile spacing reasonably within the safety limit to obtain a more economical design. The conclusions in this thesis mainly included:(1)For the pile group foundation, the displacement and stress of piles and soil are lager than the single pile.(2)The displacement and stress of piles and the displacement of soil reduce by the decrease of rigidity ratio, but the stress of soil increase.(3)With the decrease of the pile spacing, the displacement of piles and soil become small, but the axial force of pile becomes lager.(4) When the pile spacing are 2d and 2.5d, the behavior of pile group foundation are similar.