小间距高速铁路隧道群设计技术

Design Technology of High-Speed Railway Tunnel with Small Spacing

三洞并行小间距隧道设计施工时,需要根据并行线间距确定合理的相互干扰段落,针对不同的段落采取相应的施工方法,确保相邻隧道及自身的安全。赤喀客专北京联络线与京沈正线隧道小间距、长段落并行、薄土柱跨越。为减少联络线隧道对京沈客专正线在建隧道的影响,确定出联络线隧道与京沈客专同侧线间距小于45m的段落为同期施工段落。线间距小于25m,隧道全断面采用单臂掘进机机械开挖;线间距介于25~45m,采取单臂掘进机机械开挖与控制爆破相结合的措施。针对机械开挖与控制爆破相结合的开挖方式,探讨不同线间距段落的开挖方法及控制标准,为今后类似隧道的勘测设计及施工提供借鉴。

During the design and construction of three parallel tunnels with small spacing,it is necessary to determine reasonable interference sections according to the parallel line spacing,and take corresponding construction methods for different sections to ensure the safety of adjacent tunnels and their own.The Beijing connecting line of Chika passenger dedicated line and the tunnel of Beijing Shenyang main line are small spacing,long section parallel and thin soil column crossing.In order to reduce the influence of the connecting line tunnel on the tunnel under construction on the main line of Beijing Shenyang passenger dedicated line,it is determined that the section where the distance between the connecting line tunnel and the same side line of Beijing Shenyang passenger dedicated line is less than 45 m is the same construction section.The distance between the lines is less than 25 m,and the whole section of the tunnel is excavated by single arm roadheader;the distance between the lines is between 25~45 m,and the measures of combining the mechanical excavation of single arm roadheader with controlled blasting are taken.In view of the combination of mechanical excavation and controlled blasting,this paper discusses the excavation methods and control standards of different line spacing sections,so as to provide reference for the survey,design and construction of similar tunnels in the future.