Discriminant Of Weak Rock Tunnel Face Stability And Deformation Control Technology

In recent years, as China’s high-speed rail technology continues to developing, toovercome the aerodynamic problems caused by high-speed train running in thepassenger line tunnel, large section tunnel is increasing. Due to the poor groundconditions, for the weak surrounding rock, it requires tunnel face itself put forwardhigher of stability. And in the construction the stability of the working face or not willhave an important impact to the stability of the entire tunnel. Currently, the researchtunnel face deformation characteristics, stability discriminant and other aspects ofdiscrimination is still in the exploratory stage. The corresponding systematic researchand the applicability are not strong, and there is a certain gap between the actualrequirements.Firstly, on the basis of previous studies, the development of the and thedisplacement, stress distribution of the rock ahead of the face is studied. In addition,the the main affect factors of extrusion deformation of tunnel face is summarized.Base on the study of the effects of excavation in rock, use the most developedANSYS FEM software in underground projection, the plane stress release method isused step by step. Finding out the relationship between tunnel face extrusiondeformation and the release rated. Using catastrophe theory find out the release ratewhen the tunnel face extrusion displacement sudden change. Then the limitdisplacement can be found.The tunnel face stability control concepts and theoretical basis is proposed. Inaddition, the tunnel face stability control technologies of soft rock is summaried. Thecontrol principle, machinery and equipment, suitable geological conditions is alsoelaborated in the text.