超大跨度隧道三台阶+上台阶CD组合开挖施工技术  

Construction Technology of Large-Span Tunnel Using Three-Step and Upper Step Method with CD Combination

作　　者：姚加焕 YAO Jiahuan

机构地区：[1]中铁十六局集团第三工程有限公司,浙江湖州313000

出　　处：《浙江建筑》2025年第2期51-56,共6页Zhejiang Construction

摘　　要：为解决超大跨度隧道安全快速施工的难题,提出了超大跨度隧道三台阶+上台阶CD组合开挖施工技术。该技术将CD法的上台阶应用于微正台阶法中的上台阶。上台阶通过增设临时侧壁和临时仰拱,切分成两个区域开挖;中台阶和下台阶则采用微正台阶法施工。通过分步爆破有效地减少爆破施工对围岩的扰动,控制超大跨度隧道沉降变形,提高工效。在隧道仰拱施工中配套使用自行式液压仰拱栈桥,有助于围岩和初期支护共同的承载结构尽快形成,从而提高隧道施工的安全性。还研制了一种新型隧道逃生管道,适用于台阶法施工险情发生时快速撤离。In order to solve the difficult problem of safe and rapid construction of extra large‑span tunnels,a CD combination of three‑step and upper‑step excavation construction technology for extra large‑span tunnels is proposed.This technique applies the upper step of CD method to the upper step in micro positive step method.The upper step is cut into two areas by adding temporary sidewalls and a temporary inflected arch.The middle and lower steps were constructed using the micro‑orthogonal step method.The step‑by‑step blasting effectively reduces the disturbance to the surrounding rock,controls the settlement and deformation of the large‑span tunnel,and improves the work efficiency.The use of self‑propelled hydraulic arch trestle in the construction of tunnel up‑arch helps to form the common bearing structure of surrounding rock and initial support as soon as possible,thus improving the safety of tunnel construction.A new type of tunnel escape pipe is also developed,which is suitable for rapid evacuation in case of dangerous situations in the construction of step method.

关 键 词：超大跨度隧道 临时侧壁 临时仰拱 沉降变形 逃生管道 

分 类 号：U455.4[建筑科学—桥梁与隧道工程]