土体泊松比对压入管桩单桩挤土位移场的影响

Influence Analysis of Poisson Ration of Soil on Compacting Displacement Field of Single Press-in Pipe Pile

基于ABAQUS有限元软件,采用主从接触算法模拟桩-土相互作用、修正剑桥模型作为土体本构模型,通过在桩顶施加竖向位移荷载以及合适的网格划分技术建立了较为符合压入管桩压桩实际的有限元模型。利用得到的有限元模型模拟了压入管桩压桩产生的挤土位移场,对不同泊松比时压入管桩单桩挤土位移场进行了对比分析。结果表明:不同泊松比时竖向和水平挤土位移场沿深度方向和径向的分布规律趋于一致;土体泊松比的变化会对压入管桩压桩产生的竖向和水平挤土位移场产生较大影响;泊松比越大,压桩产生的竖向和水平挤土位移越大。

On the basis of the finite element software ABAQUS, an appropriate finite element model which adopts contact algorithm to simulate the interaction between pile and soil and utilizes the modified Cambridge model as the constitutive model of soil is given according to the actual piling process of press-in pipe pile through vertical displacement loading on pile top and suitable mesh technology. The pile-sinking process is simulated and the compacting displacement field is studied through this new finite element model. The comparative analysis of compacting displacement field of single press-in pipe pile is carried out under different Poisson rations of soil. The result shows that the distribution rule of vertical and horizontal displacement with the radial distances or with the depths at different Poisson rations tends to be same. The variation of Poisson ration of soil could greatly affect the vertical and horizontal compacting displacement field caused by the pile-sinking of press-in pipe pile. The bigger Poisson ration of soil is, the bigger vertical and horizontal compacting displacements are.