Study on compaction effect of jacked pile in sand

Abstract：A three-dimensional model of jacked pile was established based on the finite element simulation software ABAQUS to study the compaction effect of jacked pile when it was driven into sand.Because of the large deformation, displacement nonlinearity and material nonlinearity, Mohr-Coulomb yield criterion was adopted and the displacement penetration method was used to realize the continous penetration of jacked pile, and the feasibility of numerical simulation was verified by indoor physical model test.The simulation results were analysed and the curves of stress and displacement on different paths in the process of pile sinking were obtained.The results showed that the vertical and horizontal displacements of the topsoil reached the maximum values at the pile diameter 1.2 times from the pile axis when the depth of piling was 5 times the pile diameter;with continous penetration of jacked pile, the maximum horizontal and vertical displacements of the soil increased gradually, the growth rate tended to be gentle;the horizontal and vertical stresses increased first and then decreased with the increase of the depth of piling, and obvious stress concentration phenomenon appeared at the pile tip;the soil stress decreased rapidly with the increase of radial distance.

Keyword：jacked pile;numerical simulation;compaction effect;displacement field;stress field;