虎跳峡分岔隧道大断面施工工法优化研究  

Optimization Research on Large Section Construction Method in Hutiaoxia Bifurcated Tunnel

作　　者：张海太 李晓冉 ZHANG Haitai;LI Xiaoran(Yunnan Lixiang Expressway Investment Development Co.,Ltd.,Kunming,Yunnan650217,China;Department of Geotechnical Engineering,College of Civil Engineering,Tongji University,Shanghai 200092,China;Key Laboratory of Geotechnical and Underground Engineering of the Ministry of Education,Tongji University,Shanghai200092,China)

机构地区：[1]云南丽香高速公路投资开发有限公司,云南昆明650217 [2]同济大学土木工程学院地下建筑与工程系,上海200092 [3]同济大学岩土及地下工程教育部重点实验室,上海200092

出　　处：《施工技术》2021年第12期121-125,共5页Construction Technology

基　　金：山区高速公路地下互通立交建设与运营安全关键技术研究(云交科教201840)。

摘　　要：虎跳峡地下立交隧道断面大、变截面多,且洞内分岔匝道支洞属国内首例。该工程超大断面隧道截面最大外凸处开挖跨度达28.96m,拱顶呈扁平状,施工时易引起围岩松弛失稳、坍塌。为确保隧道开挖安全及按进度完成施工,采用右侧壁导坑先行后中导洞开挖的方法,对超大断面Ⅳ级围岩进行加强支护。相比双侧壁导坑法,开挖工期减少50d,大幅提高施工效率。通过分析监测数据,表明此工法切实可行,能满足施工要求。Hutiaoxia underground interchange tunnel has large and variable cross-sections with a branch tunnel, which is the first case in China. The excavation span of the largest convex part of the super-large cross-section tunnel is 28.96 m, and the vault is flat. It is easy to cause the instability and collapse of surrounding rock during construction. To ensure the safety of the tunnel excavation and the completion of the construction on schedule, the right-side pilot excavation is excavated before completing the middle pilot tunnel, the support of grade Ⅳ surrounding rock is strengthened. Compared with the originally designed double-side pilot excavation method, the construction period is reduced by 50 days, which greatly improves the construction efficiency. The analysis of the monitoring data shows that this construction method is feasible and can meet the construction requirements.

关 键 词：隧道 开挖 安全 支护 监测 

分 类 号：TU758.11[建筑科学—建筑技术科学]