青海丹东隧道洞口饱和黄土段施工技术研究

发布时间：2018-02-01 09:18

本文关键词： 隧道工程黄土路堑边坡饱和软黄土地基钢管桩旋喷桩　出处：《长安大学》2015年硕士论文　论文类型：学位论文

【摘要】：目前,为了适应国民经济发展的需要,国家加大了在基础设施建设方面的投入,其中,公路和铁路占了很大一部分比重。在这些已建和在建的公路和铁路中,隧道占了一定的比重,而隧道的洞口施工一直是隧道工程中的一个重点和难点,特别是地质条件不好的地区。相比于隧道的其他部分,洞口段围岩风化程度较严重,节理比较发育,经常存在断层、破碎带等诸多对工程不利的地质构造,浅埋偏压现象比较普遍。伴随着大断面隧道建设工程的增加,隧道洞口段的施工问题也开始凸显出来,如何实现隧道安全高效地进洞变得越来越重要。本文在总结国内和国外关于隧道洞口施工研究现状的基础上,结合丹东隧道的具体问题,如出口段已开挖的边坡发生滑坡,仰坡坡面支撑不住,边坡底部及明洞基础下13m~14m存在饱和软黄土,地基承载力不能满足设计要求,隧道左侧存在暗埋天然气管道以及洞口右侧K38+070位置处存在与隧道轴线基本正交的天然冲沟等,开展相应施工技术研究。研究指出采用钢管旋喷桩加固开挖的路堑边坡;配合采用桩基础加连系梁加固明洞地基;采用竖直旋喷桩加固暗洞软基配合水平旋喷桩加固掌子面软黄土可以满足设计施工要求;采用延长明洞长度配合引排水设施降低天然冲沟对隧道的影响等措施,经实际检验效果良好。通过现场研究和技术方案改进及施工措施控制,解决了丹东隧道洞口段存在的工程问题和隐患,保障了隧道及周边的安全,为今后类似工程问题提供了很好的借鉴作用,也为理论研究提供了很好的工程实例。
[Abstract]:At present, in order to meet the needs of national economic development, the state has increased investment in infrastructure construction, of which roads and railways account for a large proportion. Tunnel accounts for a certain proportion, and tunnel hole construction has always been a key and difficult point in tunnel engineering, especially in areas with poor geological conditions, compared with other parts of the tunnel. The weathering degree of surrounding rock in Dongkou section is more serious, the joints are relatively developed, and there are often faults, broken zones and many other unfavorable geological structures to the engineering. The phenomenon of shallow buried bias is common. With the increase of large section tunnel construction project, the construction problem of tunnel entrance section is also beginning to highlight. How to realize safe and efficient tunnel entry has become more and more important. Based on the summary of domestic and foreign research on tunnel entrance construction, this paper combines the specific problems of Dandong tunnel. If the excavated slope in the exit section has a landslide, the slope surface can not be supported, there is saturated soft loess at the bottom of the slope and under the foundation of the open hole, so the bearing capacity of the foundation can not meet the design requirements. There are hidden natural gas pipelines on the left side of the tunnel and natural gullies on the right side of the tunnel mouth, which are basically orthogonal to the tunnel axis, and so on. It is pointed out that the steel pipe rotary jet pile is used to reinforce the excavated cutting slope. To reinforce the foundation of Ming cave with pile foundation and tie beam; The vertical rotary jet pile can be used to reinforce the soft foundation of dark tunnel and horizontal rotary jet pile to reinforce the soft loess on the palm surface can meet the requirements of design and construction. Measures such as lengthening the length of the tunnel with drainage facilities to reduce the impact of natural gullies on the tunnel have been proved to be effective through field research technical scheme improvement and construction measures control. It solves the engineering problems and hidden dangers in the entrance section of Dandong Tunnel, ensures the safety of the tunnel and its surrounding area, provides a good reference for similar engineering problems in the future, and provides a good engineering example for theoretical research.
【学位授予单位】：长安大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：U455.4

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