Research Of Hydraulic Pressure Tunnel Lining Reinforcement Method

In the hydraulic pressure tunnel, the lining and the rock load distribution ratio changes will take place in three stages with the water pressure increases:â‘ lining does not crack, and the rock at the elastic stage;â‘¡lining does not crack, some of the rock into the plastic phase;â‘¢lining cracks, rock into the plastic phase. Of existing norms, the use of reinforced concrete lining method can be summed up in two ways:"Boundary value method" and the "formula method." "Boundary value method " applies to the situation of lining did not crack; "formula method" takes into account the lining cracking, but not very well reflect the actual load-sharing characteristics of the lining and the surrounding Rock after the lining cracking.After discussed the advantages and disadvantages of the "Boundary value method" and the "formula method" in detail, a model is established in this paper, which could show the practical characteristics of hydraulic pressure tunnel and the surrounding rock, concrete and steel bear the water pressure united after the lining cracked. Demonstrated the application of the model conditions and boundary conditions, and use the finite element method to solve it. Engineering examples be quoted to describes the calculation process and the results evaluation method of this method. And compare the calculation results with the FEM method and the traditional method, analysis the advantage of the FEM method compare to the traditional method in practical engineering application.As the calculation model and the calculation process of the finite element method is so complex when taking into account the lining crack, the promotion and application of this method may have difficulties. So this paper presents "parameter analogy method", which could use the known results section to calculation reinforced concrete lining of the new tunnel. And the change orderliness (The change orderliness of the FEM lining reinforced results about concrete marking, lining thickness, tunnel diameter, rock lithology and the water pressure.) for "parameter analogy method" were studied.