沉桩过程土体超静孔隙水压力变化规律研究

从空间圆孔扩张理论出发,提出了超静孔隙水压力随径向和深度方向变化的分布公式;并结合弹塑区连续理论,给出了沿深度线性增加,沿径向对数衰减的简化计算公式。同时考虑到沉桩速率对超静孔隙水压力的影响,结合圆孔扩张理论,推导获得沉桩时产生的孔隙水压力与沉桩速率之间的关系;并利用abaqus有限元对沉桩过程土体超静孔隙水压力变化进行数值分析,对工程中静压桩施工的控制,合理安排沉桩流程、沉桩速率,有一定的实际意义。

Research on the variation of soil excess pore-water pressure in pile sinking process

The distribution formula of excess pore-water pressure changing in the radial direction and depth was proposed on the basis of cavity expansion theory. And a reduced calculation formula that the pressure Increases linearly along the depth and appear radially logarithmic decrement was put forward combined with the elastic-plastic zone continuous theory. Simultaneously, given the effect of pile sinking rate on the pressure, the relationship between pile sinking rate and the pressure was deduced combined with the cavity expansion theory. Finally, a numerical analysis was carried out to analyze the change of excess pore-water pressure in pile sinking process with the use of abaqus finite element. The result has certain practical significance to static pile construction project control, such as reasonable arrangements for pile sinking process and pile sinking rate.