桩-土-承台非线性工作机理的模型试验

通过单桩、单板和带承台单桩的系列模型试验,对天然地基中土体的破坏规律进行分析,发现附加应力影响深度主要取决于筏板尺寸和土的性质而与荷载大小无关;对承台板对桩承担荷载能力的影响分析表明,承台板对桩端阻力的发挥有着增强作用,对桩侧摩阻力的发挥有着减弱的作用;结合土体中附加应力场的变化状况,对桩、土非线性的受荷性状给予描述,发现在带承台单桩受荷过程中,桩先进入非线性状态,然后净承台再进入非线性状态,研究结果表明,这主要是由土的塑性区开展进程所决定的。

MODEL TEST OF PILE-SOIL-CAP NONLINEAR WORKING MECHANISM

Through the series model tests of single pile,raft and single pile with cap,the conclusion that the influencing depth of additional stress is determined by the dimension of the raft and the characteristic of the soil is drawn;the strengthening or weakening action of the cap is analyzed,the cap can strengthen the pile bearing capacity of tip and weaken the pile bearing capacity of skin;considering of the changing of additional stress field,the nonlinear behavior of pile and soil is depicted and the failure pattern is concluded: firstly,the single pile with cap gets into the nonlinear state in the bearing progress,then,the net cap gets into the nonlinear state,all this is determined by the progress of the soil plastically deforming.