寒区普速单线铁路隧道下穿既有高速公路的防冻排水设计与施工

Design and Construction of SD Single-Line Railway Tunnel beneath Existing Expressway in Cold Area and Frost-proof Drainage

塘巴湖隧道是一座位于严寒地区的单线普速铁路隧道,其特点是隧道断面较小,其中心深埋水沟、深埋环向盲沟及隧底横沟等防冻排水系统均需要置于冻结线以外;浅埋下穿既有高速公路且隧道所在地层为硬质花岗岩,需要爆破施工等。围绕"寒区隧道防冻排水是重点"的原则,兼顾下穿既有高速公路安全控制措施,特别是设置中心深埋水沟、深埋盲沟以及为了满足有砟隧道运营要求,中心深埋水沟配套检查井结合避车洞设置在隧道侧壁,使中心深埋水沟埋置深度达到3.2m,隧道的设计与施工均遇到较大的困难和挑战,通过设计优化、施工工艺改进以及新型保温材料的应用研究,最终顺利完工。它的成功实施对类似工程有较强的参考价值,提出的建议也是从实践中总结的有益总结。

Tangbahu tunnel is a SD single-line railway tunnel located in cold area.Its cross section is small.The frost-proof drainage systems such as deep-buried ditches,deep-buried circular blind ditches and cross ditches at the bottom of the tunnel need to be placed outside the frozen line;the shallow-buried ones beneath the existing expressways and the stratum of the tunnel with hard granite need blasting construction.Focusing on the principle of "Frost-proof drainage of tunnel in cold area is the key point",taking into account the safety control measures of existing expressways,especially the deep-buried ditches and central blind ditches,and in order to meet the operation requirements of ballasted tunnels,the auxiliary inspection wells of central deep-buried ditches and the vehicle-avoiding tunnels are set on the side walls of tunnels,the buried depth of central deep-buried ditches will reach 3.2m,so the design and construction of tunnels will encounter greater difficulties and challenges.Through the design optimization,construction process improvement and application research of new insulation materials,the completion is finally successful.Its successful implementation has a strong reference value for similar projects,and the proposed suggestions from practice are also very useful.