地下铁路工程双侧掘进法的断面开挖顺序技术优化研究

Research on Optimization of Section Excavation Sequence Technique of Double-side Excavation Method for Underground Railway Project

文中根据地下铁路工程实际情况对传统双侧掘进法的断面开挖顺序进行优化,采用Midas/GTS软件进行有限元分析,计算两种不同断面开挖顺序下地面沉降和支护结构的位移和内力。试验结果表明,方案Ⅱ和方案Ⅰ的拱底沉降值变化差距较小,平均数值分别为0.53和0.38 mm,且方案Ⅱ拱顶,横向通道下部导洞的开挖对隧道初期支护的位移影响较小。方案Ⅱ的拱顶和左右拱脚的沉降值分别比方案Ⅰ低4.6%、77.8%和44.1%,且优化后的施工方案不仅保证隧道结构的安全性和稳定性,还能极大提高施工效率,可为类似工程条件下的隧道施工提供参考。

This article optimizes the excavation sequence of the traditional double-sided excavation method based on the actual situation of underground railway engineering.Using Midas/GTS software for finite element analysis,calculate ground settlement and displacement and internal forces of support structures under two different excavation sequences of cross-sections.The experimental results show that there is a small difference in the settlement values of the arch bottom between Scheme Ⅱ and Scheme Ⅰ,with average values of 0.53 mm and 0.38 mm,respectively.In addition,the excavation of the arch top and lower guide tunnel of Scheme Ⅱ has a relatively small impact on the displacement of the initial support of the tunnel.The settlement values of the arch crown and left and right arch feet in Scheme Ⅱ are 4.6%,77.8%,and 44.1% lower than Scheme Ⅰ,respectively.The optimized construction plan not only ensures the safety and stability of the tunnel structure,but also greatly improves construction efficiency,providing construction reference for tunnel construction under similar engineering conditions.