静压桩连续贯入机理的数值仿真

Numerical simulation of continuous penetration mechanism for jacked piles

结合有限元软件ABAQUS在处理大变形、接触非线性上的独特优势,采用位移贯入法和Mohr-Coulomb屈服准则,考虑了土体的弹塑性本构关系、接触面类型、土体初始应力场的影响等,建立静压桩连续贯入土体的有限元模型,探讨了沉桩过程中的桩周土体的应力与变形的分布特征,实现了静压桩的连续贯入过程,明确了沉桩过程中的挤土效应,得到了贯入过程中侧摩阻力及贯入阻力随深度变化规律,并将实测值与模拟值对比分析,结果相吻合。研究成果可为工程实践提供借鉴与参考。

Combining with the unique advantages of the finite element software ABAQUS on dealing with large deformation and non-linear contacts, by using the displacement penetration method and Mohr- Coulomb yield criterion, the elastic-plastic constitutive relation of soil, the contact surface type and the initial stress field of the soil are taken into account, and the finite element model for jacked piles with continuous penetrating is established to discuss the distribution characteristics of stress and deformation of soil around the pile during pile sinking process. The continuous penetration process of jacked piles is realized, and the soil squeezing effect in the process of pile sinking is clarified. The variation laws of the lateral friction resistance and penetration resistance with depth are obtained, and the measured values are compared with the simulated values. The results of the study could provide the reference for engineering practice.