摘要
山岭隧道因地形地貌条件限制,洞口往往不可避免处于半明半暗,偏压等不利地形中,给隧道洞口施工带来很大安全风险和技术难题。传统施工方法采用大开挖刷坡及加强洞口支护设计,不仅使洞口上方围岩受扰动程度大,还额外增加很大的工程量及成本。本工程通过优化设计,采用一种浅埋偏压地形中非对称式护拱进洞开挖方法,具体的施工工艺流程为施工不对称护拱基础、施工护拱、暗洞开挖、洞口衬砌施作、洞顶反压回填。非对称式护拱减少了对隧道洞口的开挖,洞口无需进行大量边坡防护,大大节省施工工期及成本。半明半暗盖挖进洞施工方法适用于公路与铁路山岭隧道进出口、浅埋段及偏压部位的隧道洞口施工。
Due to the limitation of topographic and geomorphological conditions, the tunnel entrance is often inevitably in half-bright, half-dark, bias and other unfavorable terrain, which brings great safety risks and technical difficulties to the tunnel entrance construction. In the traditional construction method, we adopt the design of large excavation, slope brushing and strengthening the support of the entrance. The previous design and construction methods not only easily cause the surrounding rock above the entrance to be disturbed, but also increase the amount and cost of the project. Through optimum design, an asymmetric arch protection excavation method in shallow buried bias terrain is adopted in this project. The concrete construction technology is asymmetric arch protection foundation, construction arch protection, excavation of underground cave, construction of tunnel lining and back-pressure backfilling at the top of the cave. Asymmetric arch protection reduces the excavation of the tunnel entrance, and the slope of the entrance does not need a lot of slope protection, which greatly saves the construction time and cost. The construction method of half-bright and half-dark cover excavation is suitable for the tunnel entrance construction of highway and railway mountain tunnel, shallow buried section and eccentric pressure part.
作者
苑雪飞
Yuan Xuefei(China Railway 16^th Bureau Group 5^th Engineering Co. Ltd., Tangshan Hebei 063000, China)
出处
《铁道建筑技术》
2019年第7期92-95,104,共5页
Railway Construction Technology
基金
中铁十六局集团有限公司科技研究开发计划项目(K2014-10C)
关键词
浅埋
偏压
非对称
护拱
工艺措施
shallow buried
bias
asymmetry
retaining arch
technological measure
