被动受荷桩成拱效应及三维数值分析

采用三维有限差分法,分析了被动受荷桩的成拱效应。建立了三维数值分析模型,考虑不同桩间距,不同堆载大小和不同边界条件等情况下,被动受荷桩对土体侧向位移的遮拦效应。分析结果表明:土体的成拱效应和桩间距关系密切,在较小的桩间距条件下,土体成拱效应明显,桩的存在有效限制了土体的侧向变形;三维情况下被动受荷桩的成拱效应与二维情况下没有太大差别,但在其他条件相同时,二维情况下桩周土体的应力明显比三维大。

Soil arching effect on passive piles and 3-D numerical analysis

Finite difference method is employed to analyze soil-arching effect on passive piles.Considering the influence on passive piles by various factors,such as pile space,loading,and boundary conditions,a 3-D numerical model was created to study the soil arching effect.The analysis results show that the pile space has a pronounced effect on soil arching.When the pile space is at a certain limiting value,the arching effect becomes apparent and the existence of passive piles can block the soil to deform in the lateral direction.Besides,there is no significant difference in analysis results whether one is to use 3-D or 2-D numerical model.However,when other conditions remain the same,stresses in soil around piles calculated from the 2-D model appear to be greater than those obtained from a 3-D model.