暗挖地铁车站拱盖法关键施工技术

Key Techniques of the Arch-Cover Method for Bored Metro Stations

  • 摘要: 针对中风化板岩强度较高、围岩稳定的特点,大连地铁在国内首次创新采用了拱盖法施作浅埋暗挖大跨车站并取得了成功。文章根据大连地铁中山广场站的设计施工情况,通过与PBA工法的对比,阐述了拱盖法的核心思想及其优缺点;并对拱盖法暗挖地铁车站初期支护扣拱后,全逆作、半逆作半顺作以及全顺作三种施工顺序在安全、质量、进度以及附加措施等方面进行了详细分析比较。分析结果指出,在没有成熟经验和相关数据支持的情况下,全逆作方案无疑是稳妥可靠的;针对大拱脚施工、扣拱施工、钻爆法施工、中板施工,以及钢管柱保护与高边墙围岩支护等关键技术问题应采取相应对策;拱盖法有待进一步优化和改进。

     

    Abstract: Considering the great strength and stability of medium weathered slate, the innovative arch-cover method was successfully adopted for the first time in construction of the large-span shallow-buried bored metro stations of the Dalian metro project. Based on the design and construction of the Zhongshan Square station, the core concept and advantages and disadvantages of the arch-cover method are compared with the PBA method in this paper. After completion of the primary support at the arch, the three different construction sequences of top-down, semi-top-down and semi-bottom-up, and bottom-up were analyzed and compared in detail from the aspects of safety, quality, progress, and additional measures. Results show that the top-down method was undoubtedly the most reliable when experience and relevant data are lacking. Countermeasures against construction problems, such as a large arch spring, arch support, medial plate, drill-blasting, and steel pipe column protection, as well as surrounding rock support for the high side wall, are put forward. Finally, the optimization suggestion of the arch-cover method is presented.

     

/

返回文章
返回