考虑变形协调的锚杆复合土钉墙变形计算方法

Deformation calculation method of anchor composite soil nailing wall considering deformation coordination

既有土钉墙内力变形计算方法多基于静力平衡理论提出,但是其计算结果未能揭示土钉墙内力和变形的发展规律。文章通过假定滑动面的位置,基于Mindlin解考虑变形协调条件建立了锚杆复合土钉墙内力及变形计算方法,揭示了锚杆复合土钉墙的变形及内力随深度的变化规律。结果表明:复合土钉墙中锚杆轴力较小且变形控制作用较好,其中面层力对限制基坑支护结构变形发挥重要作用;锚杆上被施加的预应力可分担其他杆件的支护压力,达到控制整体变形的作用,锚杆的特殊受力形式也可分担土压力,使得复合土钉墙支护效果优于普通土钉墙;对比分析的理论结果与工程实测数据,可验证这一计算方法的合理性。

The existing calculation methods of internal force and deformation of soil nailing wall are mostly based on the static equilibrium theory,but the calculation results fail to reveal the development law of its internal force and deformation.This paper establishes the calculation method of the calculation method of the internal forcc and deformation of the anchor composite soil nailing wall by assuming the position of sliding surface and considering the deformation coordination based on Mindlin solution and reveals its change law with depth.The results show that the inner force of anchor is small and the deformation control effect is good,and the surface force plays an important role in limiting the deformation of foundation pit of supporting structure.The prestress applied on the anchor can share the supporting pressure of others to control the overall deformation.The stress form of the anchor can also share the earth pressure,so that the supporting effect of the composite soil nailing wall is better than that of the ordinary soil nailing wall.The results from comparative analysis and measured data can verify the rationality of the calulation method.