为研究不同开挖宽度对基坑 L 形转角区支护结构变形规律的影响,基于滨州市某异形深基坑工程项目的现场实测数据,分析了基坑开挖过程中 L 形转角区阴阳角位置处支护结构变形规律的差异性;建立了不同基坑宽深比(B/H,B和H 分别为基坑宽度和深度)的 L 形转角基坑模型,研究了不同宽深比条件下转角位置处阴阳角相互作用条件下支护桩水平变形的空间分布规律,进一步明确基坑L形转角区支护桩不同深度处水平变形受影响范围.结果表明:当B/H<1.0 时,阳角侧支护桩浅部水平变形受转角效应影响的范围随B/H 的增加呈现出明显减小的趋势,其值近似满足 2.4H-B;当B/H>1.0 时,阳角侧支护桩浅部水平变形受转角效应影响的范围约为1.5H;坑内底部支护桩水平变形受基坑宽深比影响不明显,受转角效应影响的范围约为 0.6H;当B/H<1.0 时阴角侧支护桩浅部水平变形受影响范围约为 1.6H,当B/H>1.0 时其水平变形受影响范围约为 0.6H+B;坑内开挖底面位置处阴角侧支护桩水平变形受影响范围约为 0.6H+B,受宽深比变化影响不明显.
Study on influence of excavation width on deformation of supporting structure in L-shaped corner area of shaped foundation pit
In order to study the influence of different excavation widths on the deformation law of the supporting structure at the L-shaped corner area of the foundation pit,based on the field measurement data of a shaped deep foundation pit project in Binzhou city,the variability of the deformation pattern of the supporting structure at the negative and positive corner positions during the excavation of the foundation pit was analyzed.The L-shaped corner pit model with different width-to-depth ratios(B/H,B and H are the width and depth of foundation pit respectively)of foundation pit was established,the spatial distribution law of the horizontal deformation of the supporting piles under the conditions of interaction between the negative and positive corner under different width-to-depth ratios was studied.The affected range of horizontal deformation of the supporting piles at different depths in the L-shaped corner area of the foundation pit was further clarified.The results show that when B/H<1.0,the range of the horizontal deformation of the shallow part of the supporting piles on the positive corner side affected by the corner effect shows a clear tendency to decrease with the increase of B/H,its value approximately satisfies 2.4H-B.When B/H>1.0,the horizontal deformation of the shallow part of the supporting piles on the positive corner side is affected by the corner effect in a range of about 1.5H.The horizontal deformation of the supporting piles at the bottom of the pit is not significantly affected by the width-to-depth ratio of the foundation pit and is affected by the corner effect in a range of about 0.6H.When B/H<1.0,the horizontal deformation of the shallow part of the support piles on the negative side is affected in a range of about 1.6H,and when B/H>1.0,its horizontal deformation is affected in a range of about 0.6H+B.The horizontal deformation of the support piles on the negative side at the location of the bottom of the excavation in the pit is affected in a range of about 0.6H+B,which is not obviously affected by the change of the width-to-depth ratio.
shaped foundation pitdeformation patternnumerical simulationcorner effect
NETL
NSTL
万方数据
