公路下方隧道开挖涉路工程分析及控制要点

Analysis and control points of road-related engineering in tunnel excavation under highway

依托某处新建的铁路隧道下穿公路(隧道、桥梁、路基)三种不同断面工程建设项目,采用有限元软件Midas GTS建立模型,结合施工现场地质、施工条件、高速公路与隧道的位置等关系,建立分析模型,进行相应的分析论证。经分析,在通行的高速公路下方进行隧道开挖作业,路基处位移相对隧道、桥梁下方开挖较大。针对道路下发开挖隧道,采用超前支护,结合地质情况采用分台阶开挖,进行必要的沉降、变形监测等手段,可以确保道路下方隧道开挖安全。

Relying on the construction project of three different sections of the road(tunnel,bridge,subgrade)under a new railway tunnel,the finite element software Midas GTS is used to build the model,combined with the construction site geology,construction conditions,the location of the highway and the tunnel relationship etc,establish an analysis model,and carry out corresponding analysis and demonstration.After analysis,tunnel excavation is carried out under the passing expressway,and the displacement of the roadbed is larger than that of the excavation under the tunnel and bridge.For the tunnel excavation under the road,the use of advanced support,combined with the geological conditions,the use of stepby-step excavation,and the necessary settlement and deformation monitoring,can ensure the safety of tunnel excavation under the road.