基于收敛-约束法的隧道衬砌施作时机探讨

Reasonable Installation Time of Tunnel's Lining Based on Convergence-Confinement Method

作为新奥法施工的重要组成部分,二次衬砌对隧道工程质量起着至关重要的作用,但目前没有很好确定二次衬砌支护时机的方法,通常采用以经验类比所得分级为主,以数值模拟得到数据为辅的设计方法.收敛-约束法是一种新兴的支护方法,与传统方法不同,该方法重点考虑支护与围岩之间的相互作用,并利用弹性力学原理研究二者之间的互相动态作用,得出支护时机的理论解.运用该方法可以得出二次衬砌施做时机的参考值,可为类似工程参考.

As an important component of NATM Tunnel,the secondary lining plays a vital role in the quality of a project.However,there is no good method to determine the appropriate supporting time of secondary lining; most of the current design methods in tunnel engineering are mainly based on the rock mass classification,with the numerical simulation used as supplement to get the data.The convergence-confinement method,a new tool developed for tunnel support design,can prove to be an effective approach to analyzing the above problem.Different from other conventional support design method,it focuses on the interaction between the support and the surrounding rock.The analytic solution of the support time is obtained by using the principle of elasticity.Using this method,we can get the reference value of the secondary lining support time,which can be used for reference for similar projects.