摘要
宁波野猪山公路隧道右线出口段埋深浅、围岩差,采用岩土控制变形工法施工。该工法在我国公路隧道施工中几乎未有使用。本文通过数值模拟和现场监测数据对比分析,得出:1)隧道地表沉降的开挖空间效应约为0.6倍跨径,并据敏感程度划分为沉降敏感区、敏感过渡区、稳定区3个区域;2)隧道拱顶沉降约60%发生在掌子面到达监测断面前,开挖空间效应稍大于单倍跨径;3)隧道掌子面挤出变形呈外凸抛物面形态,建议施工中纤维锚杆的搭接长度设为6 m,并据挤出变形发展速率划分为快速发展、稳定发展、基本稳定3个阶段。
ADECO-RS （analysis of controlled deformation in rocks and soils） method is used in Ningbo Yezhushan Highway Tunnel with shallow buried depth and weak surrounding rock. The above-mentioned method is hardly used in highway tunnel construction in China. Based on the analysis of numerical simulation and field monitoring, some results are obtained as follows ： 1 ） As for surface subsidence of Yezhushan Tunnel, the spatial effect of excavation is 0.6 times the span and the settlement area can be divided into 3 parts, namely, sensitive area, sensitive transition area, and stable area. 2 ） The spatial effect of excavation on tunnel crown top settlement is almost a span and 60% of crown top settlement occurs before tunnel face reaches monitoring section. 3 ） Three-dimensional morphology of Yezhushan Tunnel face extrusion is outer convex parabolic; lap length of fiberglass bolt is suggested to be 6 m and the development of extrusion deformation is segmented into three stages.
出处
《隧道建设》
北大核心
2017年第5期593-599,共7页
Tunnel Construction
基金
基于软弱围岩变形控制工法的公路隧道安全施工关键技术研究项目(201611)
国家自然科学基金项目(51578408)
复杂环境下浅埋大断面互通隧道关键技术研究项目(20133139)
