桩锚和土钉联合支护方案数值模拟分析

Numerical Simulation Analysis of the Pile-anchor and Soil-nailing Combined Support Scheme

以百色某棚户区改造项目深基坑工程为背景,采用PLAXIS有限元计算软件建立二维数值分析模型,对单一桩锚支护方案与桩锚土钉联合支护方案中的桩体结构变形特性进行分析。结果表明:桩锚土钉联合支护方案中的桩体水平位移、桩体弯矩以及锚索轴力均随着基坑开挖深度增加不断增大,变化速率先增大后减小;与单一桩锚支护方案相比,桩锚土钉联合支护方案对于桩体水平位移的限制效果更好,桩体所受到的弯曲应力与锚索轴力更低,对基坑周围环境影响程度更小,基坑整体安全稳定性更高。该研究结果可为以后相似的工程提供实用价值和理论研究参考。

Based on the background of a civil deep foundation pit project in Baise City,a two-dimensional numerical analysis model is established by using the finite element software PLAXIS to analyze the deformation characteristics of pile structure in the single pile-anchor support scheme and the combined support scheme of pile-anchor and soil-nailing.The results show that the horizontal displacement of the pile,the bending moment of the pile and the axial force of the anchor cable in the combined support scheme of pile-anchor and soil-nailing increase continuously with the increase of the excavation depth of the foundation pit,and the changing speed is increased after the increase.Compared with the single pile-anchor support scheme,the combined support scheme of pile-anchor and soil-nailing has better limiting effect on the horizontal displacement of the pile,lower bending stress and anchor cable axial force on pile,less influence on the surrounding foundation pit,and higher safety and stability of foundation pit.The study result can provide practical value and theoretical reference for similar projects in the future.