Research on the Excavation Method of Large Span Tunnel in Shallow Buried and Soft Rock
The excavation method of large span tunnel in shallow buried and soft rock was studied in order to provide theoretical reference for the design and construction of the tunnel engineering.The FLAC3D finite difference software is used to numerical simulate the inlet of a large span tunnel in Guangzhou by the double side drift method,cross diaphragm method (CRD) and three-bench seven-step excavation method.Comparative and analysis the subsidence value of tunnel vault,the horizontal displacement of surrounding rock,plastic zone and the maximum and minimum principal stress under these three kinds of method.The results show that double side drift method is superior to the CRD method and the three-bench seven-step excavation method in controlling the sinking of tunnel vault,horizontal displacement of the arch foot and the stress concentration of the surrounding rock.Double side drift method is similar to the CRD method,both are superior to the threebench seven-step excavation method in controlling the plastic zone of the surrounding rock.The three-bench seven-step excavation method is more prone to happen instability phenomenon of the surrounding rock than the double side drift method and CRD method.It is advisable to give priority to use the double side drift method rather than use the CRD method and the three-bench seven-step excavation method of large span tunnel in shallow buried and soft rock.
shallow buried and soft rocklarge spantunnel excavationmethodnumerical calculation
NETL
NSTL
万方数据
维普
