浅埋暗挖平顶直墙大断面隧道施工变形控制

结合北京地铁八号线安德里北街站1号风道工程,对平顶直墙大断面隧道在浅埋暗挖法施工条件下的变形及其控制措施进行分析.采用有限元分析软件ANSYS分别对2种支护方案进行模拟分析.方案一：采用格栅钢架、钢筋网加喷射混凝土的初期支护措施；方案二：在方案一基础上加设大管棚和小导管注浆超前支护措施.另外,还对模拟结果与现场监测数据进行对比分析.通过分析得出：采用方案二的支护措施施工浅埋暗挖平顶直墙大断面隧道,可以控制变形量值在要求的范围内,达到安全施工的目的.

Deformation Control of Shallow Mining Large Section Tunnel with Horizontal Roof and Upright Wall

This paper, based on No. 1 air-duct of Andeli north street station, Beijing subway line 8, analyzes the deforma- tion of large section tunnel with horizontal roof and upright wall constructed by shallow mining method. This paper simulates and analyzes two construction support programs with finite element analysis software~ Program ! took lattice girder reinforced shotcrete support measures. Program II added bassoon studio and small pipe grouting for pre-support. And it compared and analyzed simulation results and monitoring data. Through the above analysis we can conclude that the measures taken in Program II can control the deformation of large section tunnel with horizontal roof and upright wall constructed with shallow mining method within the requirements of the specification, and achieve the safe construction target.