隧道初期支护侵限段的结构安全性分析

Structural Safety Analysis of Beyond-limit Primary Support Sections on Tunnels

贵阳市北京东路0号隧道属于典型的浅埋、超浅埋大跨度连拱隧道,在施工过程中,多个段落初期支护下沉变形后侵入二衬范围。针对该现象,详细介绍了初期支护下沉及地表开裂情况。运用有限元分析软件ANSYS对初期支护侵限段进行了安全分析,并得出了二衬厚度与结构安全系数的关系。在以上分析的基础上,对隧道侵限段作了有针对性的处理,有效地指导了侵限处治施工,解决了工期紧张和成本控制问题。

Beijing east road No.0 tunnel of Guiyang is typical shallow or ultra-shallow large-span arch tunnel.During construction process,a number of primary support sections intruded into the range of the secondary lining after deformation.According to the problems,the authors introduce the condition of primary support subsidence and surface crack.Based on ANSYS program,the authors analyze the safety of beyond-limit primary support sections,and discuss the relationship between the thickness of secondary lining and the safety factor of structure,which effectively guide the treatment construction of beyond-limit primary support sections,successfully resolve the problems about the tight deadlines and cost control.