地基变形引起的高桩排架负摩擦力、内力和变形的研究

研究了将桩身杆单元与以非线性位移-反力表示的桩土单元叠加构成复合单元(桩单元)的桩结构计算方法,利用桩土侧向压力-位移、摩擦力-位移曲线,将地基滑移和沉降视为初始位移,编制了考虑地基位移、沉降引起的码头高桩排架负摩擦力、内力和变形的有限元计算程序。通过对某多级围堤接岸结构的高桩码头排架的数值分析,得出在筑堤引起的负摩擦力和土体水平滑动作用下,上部结构没有产生过大作用力,但桩基承受了很大的轴向压力和较大的弯矩,需采取一些减小负摩擦力的措施。

Study of negative frictional force,internal force and deformation of high-pile bent resulting from soil settlement and slide

A new calculating method of interaction between pile and soil is suggested in the paper.That is called "composite element method".It is composed of rod element simulating pile shaft and the element simulating nonlinear displacement and reacting force between pile and soil.By using the lateral pressure-displacement and friction stress-displacement curves between piles and soils,a FEM programme calculating the negative frictional force and internal force and deformation of high-pile bent resulted from soil settlement and slide is compiled,in which the soil settlement and slide are regarded as initial displacements.The numerical simulation of high-pile bent connecting the land with multiple-stage embankmen indicates that the action force of upper structure is normal under the negative frictional force of piles and soil slide,but very large shaft compressive stress and bending moment are developed.Therefore,some measures should be taken to decrease the negative frictional force.