桩间距对双排式钻孔抗滑桩的影响研究

Study on Influence of Pile Spacing of Double-row Drilling Anti-slide Piles

在治理推力较大的滑坡工程中常采用双排抗滑桩,为厘清桩间距的变化对双排式钻孔抗滑桩位移、内力分布以及前后排桩承担滑坡推力比例的影响,从而为双排式钻孔抗滑桩的设计和施工提供参考.采用有限元程序ABAQUS建立双排式钻孔抗滑桩的有限元三维分析模型,其它条件不改的情况下,分别改变模型中桩间距,进行单因素分析.分析表明,桩间距的变化,对双排式钻孔抗滑桩前后排桩的桩顶最大位移影响明显,桩身内力最大值位置基本不变,桩身内力的分布变化很小,而桩身内力最大值影响明显;桩间距取3 d^6 d时,既能前后排桩的土拱效应越明显,又能使前后排桩承担的滑坡推力比例差距较小,建议桩间距取3 d^6 d作为双排式钻孔抗滑桩设计参考范围.双排式钻孔抗滑桩具有施工安全、速度快、节省成本等优点,值得推广.

Double-row anti-slide piles are often used to the large-scale landslide.This paper is going to find out the influence of the change of pile spacing on double-row drilling anti-slide piles＇ displacement,internal force distribution and landslide thrust on the front and back row piles of allocation proportion,thus to provide the reference for design and construction of double-row drilling anti-slide piles.Based on the finite element program ABAQUS,three-dimensional finite element analysis of models of double-row drilling anti-slide piles are established.As conditions of models don＇t change,we change the pile spacing for univariate analysis.change the pile spacing of double-row drilling anti-slide piles have obvious influence on the displacement of pile top.The are internal force of piles maximum position remain unchanged.Changes in the distribution of pile of internal forces is small.It haves obvious influence on the maximum internal force of pile.When pile spacing is from 3d to 6d,both front and back row piles of soil arching effect is more obvious,and landslide-thrust proportion gap front and back row piles bear is smaller.So we suggest using the pile spacing from 3d to 6d in the design of double-row drilling anti-slide piles.Because double-row drilling anti-slide piles have the advantages of safety,speed,cost saving etc,so it is worth widely using.