谷竹高速公路宴家隧道变形控制工法适用性研究

A Study on the Applicability of Deformation Control Method in Yanjia Tunnel of Guzhu Expressway

在软弱的岩层、所处地应力较高、富含水等不良地质条件下开挖隧道时,很难对隧道变形进行预测和控制.为此,以谷竹高速公路宴家炭质片岩隧道工程为依托,采用三维数值模拟方法对8种不同的施工方法下围岩变形情况进行系统研究对比,就竖向位移与水平向位移的收敛情况对所涉及的几种施工方法的适用性进行讨论.数值分析结果表明,采用三台阶法、交叉中隔墙法或双侧壁导坑法比采用其他几种工法能够更有效地控制围岩变形,隧道的稳定性能得到保障.

It is difficult to control the deformation of tunnels when they are excavated in soft rock stratum,or under unfavorable geological conditions such as high ground stress or even rich in water,and it is particularly difficult to predict the deformation.In this paper,based on Yanjia Carbon Schist Tunnel of Guzhu Expressway,a three-dimensional numerical simulation model is used to study and compare the surrounding rock deformation of eight different construction methods,and the convergence of vertical displacement and horizontal displacement is discussed.The results of numerical analysis show that in the construction process of this tunnel,if the three step method,cross middle partition method or double side heading method are used,the deformation of surrounding rock can be effectively controlled and the stability of the tunnel can be guaranteed compared with other methods.