软弱围岩段连拱隧道施工安全及衬砌结构分析

该文以深圳某公路隧道为工程背景,采用有限元程序对该连拱隧道的施工过程进行了数值模拟,得到了隧道围岩的变形规律、应力分布特征,以及围岩位移随时间变化的规律。采用荷载-结构法对隧道二次衬砌内力和截面配筋进行了验算。验算结果表明:设计时可通过增大局部截面厚度和增加钢筋来提高衬砌结构强度,从而最大程度地保证隧道施工的安全进行。

Analysis on Construction Security and Lining Structure of Multi-arch Tunnel in Weak Surrounding Rock Section

With the engineering background of a highway tunnel in Shenzhen,the finite element program is used to numerically simulate the construction process of multi-arch tunnel,and achieves the deforming rule and stress distribution characteristic of tunnel surrounding rock,and the rule of surrounding rock displacement with the time change.The load-structure method is used to check the secondary lining inner force and the sectional reinforcement of tunnel.The checking result shows that the strength of lining structure can be upgraded by increasing the local sectional thickness and the reinforcing bars so as to guarantee the safe construction of tunnel at the maximum extent.