Study On Construction Mechanical Characteristics Of City Large Section Group Tunnels With Closely Spaced

Based on the engineering background of chongqing HongYanCun tunnel entrancesection, by the method of numerical simulation for large span small clear distance ofhole construction mechanical behavior of related research, by comparing the differentexcavation methods, the surrounding rock under different excavation sequence andsupporting structure of the stress and strain method to determine the optimal group ofhole excavation sequence and excavation. This thesis mainly research work specific asfollows:â‘ through the GongYanCun group of hole bottom subway station tunnel withdifferent excavation method of surrounding rock and supporting structure mechanicsbehavior of determining the tunnel with double wall pilot tunnel method is superior tocontrast the CRD method.â‘¡through the upper HongYanCun group of holes in rock and soil layer of largespan small clear distance tunnel by adopting the method of different excavationsequence and excavation when the surrounding rock and supporting structuremechanical behavior compared to come to a conclusion: in the first excavation on theleft side of the upper rock tunnel, station tunnel and left driveway tunnel with doubleside heading method for optimal excavation method; Excavation tunnel in upper soillayer on the right side, the first station tunnel and right lane tunnel with double sideheading method for optimal excavation method.â‘¢comprehensive analysis HongYanCun import group holes under differentexcavation method, the excavation sequence, between surrounding rock group, theinteraction law of force and deformation of retaining structure, get the first group of theupper hole excavation on the left side of the rock tunnel, on the right side of the soiltunnel after excavation for optimal excavation sequence.â‘£for HongYanCun import group hole under the first on the left side of the upperrock tunnel excavation sequence, the left traffic lane tunnel with double side headingmethod, right lane tunnel the CRD method is adopted for the construction of the twoChambers is the most reasonable method.