Ⅲ类围岩全断面开挖隧道喷砼最小厚度初探

Preliminary Investigation on Minimum Thickness of Shotcrete for Full Section Excavated Tunnel in Rock Class Ⅲ

喷射混凝土是隧道初期支护的重要组成部分 ,是提高支护结构整体刚度 ,有效控制围岩变形 ,改善隧道结构的应力分布状态 ,减少隧道突发性坍塌发生的重要步骤。本文用有限元静力数值分析方法 ,对青龙背隧道 类围岩全断面开挖喷混凝土厚度进行了计算分析 ,对同类工程也有一定的指导意义。

The shotcreting is a main component for primary supporting in tunnel and is an important step in enhancing the stiffness of support, controlling the deformation of surrounding rock, improving the stress distribution in tunnel structure and reducing the sudden collapse in tunnel. In this paper, the finite element static numerical analysis method was used for determining the thickness of shotcrete in Qinlongbei tunnel full face excavated in rock class Ⅲ. It can serve as instruction for similar projects. [