复合土钉支护基坑的工程实例分析

通过一个具体的工程实例,采用数值分析的方法,模拟基坑开挖过程中复合土钉支护结构的受力性状,并与实测结果进行比较,探讨影响复合土钉支护基坑侧向变形和体系内力的因素。通过有限元数值分析结果与现场实测数据对比表明,二维有限元数值分析在一定程度上能够反映现场复合土钉支护基坑开挖的变形和内力分布情况。计算结果表明:土钉中的内力与其位置有较大的相关性,顶部和底部的土钉受力较小。各层土钉轴力是在开挖下一层土体时引起的,并且随着开挖进行,土钉的轴力逐渐增大。参数分析结果表明:土钉设计参数如钉的刚度、水平间距,搅拌桩的刚度等对基坑的侧向位移有影响。

Analysis of behavior of nailing supported mixed soil-cement wall in excavation

The behavior of a nailed retaining wall was analyzed through a case by using 2D-FEM analysis.The retaining walls were used for excavation work of a building foundation.In numerical analysis,deep mixed walls and soft soils were represented by Mohr-Coulomb materials and the nails were modeled by bar elements.The calculated results were compared with the field measured values.The results show that the numerical analysis can simulate field performance fairly well.The distribution tension force in nail and effective factors such as length,stiffness,spacing of nails,and stiffness of mixed walls were discussed.The results show that the parameters of nails have great influence on the lateral displacements of the nailed walls.