联拱及超小间距隧道的设计介绍

研究目的:对联拱及小间距隧道设计施工中的一系列问题提出看法,并提供范例,供今后同类隧道设计参考。研究方法:综合介绍白云山、南京地铁、杭州解放路、小洋山等4座双联拱和超小间距隧道的设计与施工,从而总结概括出此类隧道的若干设计、施工要点。研究结果:工程经验加计算分析仍是目前隧道工程设计的主要手段。在笔者列举的工程设计中,设计者在充分吸取前人经验的基础上,通过多种计算为设计提供了定量分析的依据,施工监测信息的反馈使设计更趋完善。研究结论:联拱及小间距隧道技术能有效地缩小线间距,减少洞外征地、洞口高边坡、洞外线路高填方或引桥工程;白云山等4座隧道设计中采用的小导管或大管棚超前支护、对拉锚杆、微震爆破等对于保护围岩、发挥围岩的自承能力起到了决定性作用;在铁路下开挖隧道,须做好扣轨和巡视工作,确保铁路运营的安全;在联拱及小间距隧道的情况下,应进行施工监测。

Design of Double Vault Tunnel and Extreme Small Space Tunnel

Research purposes: Based on the examples,the ideas are expressed on the problems in the design and construction of double vault tunnel and extreme small space tunnel for the purposes of providing reference design of similar tunnels.Research methods:The comprehensive introductions are given to the design and construction of Baiyunshan,Nanjing Metro,Hangzhou Jiefanglu and Xiaoyangshan tunnels and based on which the summary is made for the key points of design and construction of similar tunnels.Research results:Nowadays the main means of design of tunnel still depends on the engineering experience and calculation.The basis for quantitative analysis of design of tunnel can be obtained by learning the previous experience and doing calculations and the feed back of information on construction can make the design more perfect.Research conclusions:Application of the technology for double vault tunnel and extreme small space tunnel can shorten midway between tracks and reduce the quantities of requisition land and high side slope at the tunnel portal and work of filling soil outside the tunnel.The small guide pipe and large pipe shed for support in advance applied in Baiyunshan Tunnel made good effects on protection of wall rock during small blast,so the wall rock can set function of self bearing capacity.In the course of excavation under track,the works of fastening rail and patrol should be done well for ensuring operation safety of railway.In the courses of construction of double vault tunnel and extreme small space tunnel,the construction monitoring should be conducted.