The Key Control Technology Of Subway Undergroud Wearing The Highway

The public traffic congestion is improving with the increase of urban population density.The underground rail transport will become an effective way to solve the problem of urban traffic congestion because of its safety,high efficiency,environmental protection and other characteristics.The construction of subway tunnel project in the city will inevitably encounter through building and content,it ’s great significance to ensure the operation safety of the existing lines by choicing reasonable construction method and supporting technology.Taking changchun subway line of wearing the XX highway as the background,we could study the construction method of wearing the highway and supporting technology through using the method of the combination of numerical simulation and monitoring measurement.Firstly,The advantages and disadvantages and applicable scope of several kinds of wearing under excavation construction technique were summarized after analyzing the wearing under excavation technique of previous engineering.The double wall pilot tunnel method and reducing shed the preliminary suppot technology is suitable to this project through the comparison and analysis to several wearing under technology.Secondly,CRD method and double wall pilot tunnel method was simulated by using finite difference software FLAC3 D.Through the comparison between the simulation and calculated value,the double wall pilot tunnel method is superior to the CRD method in the control surface subsidence and the vault settlement.Again,The mechanism,parameter design and construction methods of the reducing shed the preliminary suppot technology is instructed.The two different types of supporting technology are simulated by using FLAC3 D and the simulation numerical is compared.The results show that the reducing shed the preliminary suppot technology has more advantages over the preliminary support of the rotary jet grouting technology in the control of the surface settlement,vault subsidence.Finally,Monitoring schemes of wear under the construction are studied and the actual measured value is analyze.The changing laws of soil displacement and surface settlement of the actual construction process are foud.The double wall pilot tunnel method and preliminary suppot technology are rationality by the comparison between the actual measured value and the numerical simulation.