承台外区土阻力群桩效应及效应系数的有限元分析

利用三维弹塑性有限元方法,对复合桩基承台外区土阻力群桩效应及其效应系数进行了研究,讨论了土类、桩长、桩距、桩数等对承台外区土阻力群桩效应及其群桩效应系数的影响,结果表明(1)承台外区土阻力随承台宽与桩长之比 (B/L)的增大而增大,但增幅不大;随桩距S增大而增大;受桩数n的影响不大。(2)承台外区群桩效应系数随B/L增大几乎无变化;随S增大而增大;不随n变化而变化。(3)承台外区群桩效应系数与土类有关。

FEM analyses on effects of earth-resistence pile group in pile-cap outskirt and effect coefficient

This paper was focused on the pile group effect and its effect coefficient of soil resistance by using the three-dimensional finite element method. Some influencing factors, such as the soil type, pile size, pile distance and pile density etc., were introduced and their effects on the pile group effect and its effect coefficient of soil resistance , were deeply discussed respectively. The results indicate that: (1) the soil resistance of the pile-cap outskirt shows an tendency of increasing with the proportion of the pile-cap outskirt width (B) to the pile length (L), and the pile distance (S), while no variation with pile density (n); (2) the pile groups effect and its effect coefficient keep no variations with the B/L and n, while increase with S; (3) the pile groups effect and its efficiency are associated with the soil type.