天山寒区隧道的径向注浆施工技术应用
2018-08-30于浩
于浩
摘要: 随着国民经济的快速发展,在西部地区需要修建大量穿越天山的寒区隧道。西部地区寒冷的气候及天山山体复杂含水的地质环境,经反复冻胀影响,势必造成隧道二衬混凝土开裂,导致衬砌的承载力大幅降低等严重病害,对隧道的长期运营带来一系列恶劣影响。本文从施工角度,通过有效的径向注浆施工技术使浆液在初支后岩层裂隙内扩散充填,实现堵水加固、止水防渗目的,进而达到长期防止冻胀的使用效果。
Abstract: With the rapid development of the national economy, a large number of cold zone tunnels crossing the Tianshan Mountains need to be built in the western region. The cold weather in the western region and the complex geological environment with watery Tianshan Mountains undergo repeated frost heave, which will inevitably cause cracks in the concrete of the second liner of the tunnel, resulting in serious damage to the lining's bearing capacity, and a series of adverse effects on the long-term operation of the tunnel. In this article, from the construction point of view, the effective radial grouting construction technology is used to make the slurry diffused and filled in the fractures of the rock after initial support, to achieve water-blocking reinforcement, water stop seepage purposes, and then to achieve long-term use of frost heaving effect.
關键词: 寒区隧道;径向注浆;施工技术
Key words: cold zone tunnel;radial grouting;construction technology
中图分类号:U415.6 文献标识码:A 文章编号:1006-4311(2018)20-0153-02
0 引言
隧道的径向注浆技术是在隧道开挖后沿隧道径向钻孔注浆的工艺,通过注浆的压力扩散使岩石裂隙充分填充,使隧道周边初支背后几米范围内的软弱区形成注浆岩盘,既完成堵水又很好改良和保持隧道围岩内部的受力,提高围岩的承载力和自稳力,从理论上讲,对于大多数项目实行的新奥法施工是个有力的补充。特别是在近几十年来,随着对注浆技术认识的提高和对注浆配套装备的改良,现场施工处置的技术水平得到长足发展,现场对围岩加固和堵水效果得到大幅提升。
1 工程概况
天山某隧道某号斜井是一座控制性工程,隧道全长2.8km,位于天山北坡,进口设计高程 2408m,距离沟口约 1km,冲沟坡度为 10°左右,斜井进口段为崩积、洪积卵漂石层,表部较为松散,下部密实,卵漂石母岩成份以凝灰质砂岩、粉砂岩为主,呈棱角状,进口边坡开挖时可能出现局部坍塌。……
