隧道易切削锚杆全断面预加固的三维数值模拟

Three-dimensional Numerical Simulation for Full-face Pre-reinforcing by Free-cutting Bolts in Tunneling

隧道易切削锚杆全断面预加固工法主要是指应用易切削注浆锚杆对掌子面前方的"待挖核心体"进行预加固,以控制掌子面前方核心岩土体的变形,从而实现隧道全断面安全、顺利掘进的一种隧道工法。本文运用有限元技术,对该法施工的隧道进行三维数值模拟。分析表明,通过易切削锚杆对"待挖核心体"的预加固作用,能明显改善掘进过程中的围岩形变和力学特性。计算所得结果能为类似工程施工提供借鉴。

Full-face reinforcing by free-cutting bolts in tunneling involves using free-cutting bolts through which grouting can be conducted to reinforce the advance core to be excavated so as to guarantee the safety of tunnel excavation. This paper performed a 3-D numerical analysis for a tunnel excavated by using this method. Results indicated that the deformations and mechanical characteristics of the surrounding soils were improved through pre-reinforcing the ＂advance core＂ by free-cutting bolts. Data included in this paper can be utilized for guiding similar underground projects.