Analysis On Load Transfer Of Embankment Pile And Rigid Pile Composite-foundation With Cushion

In this paper, the embankment, pile and soil are considered as whole body. The transfer function method is improved. Reduced model of pile-spring-soil is presented. The equations of pile, soil and spring are build, iterative method is used to solute the simultaneous equations. The method considers the layered soil and nonlinear property of transfer function. It is easy to get the calculation data and figures such as participating load ratio, neutral point, displacement, axial force, friction distribution.Influencing regularities are disclosed by parametric analysis. The influencing factors include pile length, pile diameter, pile modulus, soil modulus, coefficient of the friction, etc.The influence of consolidation is analysis by the improved transfer function method and finite different method that is used to calculate the consolidation degree.There are some common and variant characteristic between the rigid pile composite-foundation with cushion and embankment pile. The negative friction appears in the upper part of pile body. The fill section and cushion have adjusting capability, the participating load ratio changes while the load level is different. The filling soil is flexible, but the cushion cap rigid. The fill section length is much grater than the cushion, thus the pile can entry the fill soil adequately.The analogous method is presented to analyze rigid pile composite-foundation with cushion, the change regularities of displacement, participating load ratio, neutral point, axial force and friction distribution, because of the variable parameter such as pile length, pile spacing, cushion thickness, cushion modulus, soil modulus, limit resistance on pile end, etc.