Analysis Of Hydraulic Fracturing For Concrete Lining Of Pressure Tunnel By Cohesive Crack Model

With the development of economy, requirement of hydropower becomes more and more severe. The potential hydro-energy resource in our country is the first in the world, but it is energy-inefficient and is uneven distribution. In order to solve the two problems, on one hand we need to build more hydropower station to increase the use of hydropower resource, on the other hand we should carry out interbasin water transfer. All these methods involve hydraulic pressure tunnel. The hydraulic pressure tunnel is the common water diverting and water conveying structure. It usually uses circular section and installs concrete lining. With the construction of high-pressure、 deep-location tunnel, the demand of design of hydraulic tunnel is more and more higher and the consequence of hydraulic fracturing in hydraulic tunnel is more and more serious. So we need to try our best to avoid the hydraulic fracturing. If it happens, we must discover it immediately and adopt remedial measures.This paper introduces the analysis of hydraulic fracturing for concrete lining on cohesive crack model. It uses heterogeneous distribution cohesive crack zone to simulate hydraulic fracturing and establishes analysis model for hydraulic fracturing of pressure tunnel. Influence of characteristic parameters of rock mass and lining characteristic parameters on the pressure of lining hydraulic fracturing are also discussed in this paper. In the end, we put forward the preventive and remedial measures about hydraulic fracturing. The main contents contains(1)Rock and lining combined bearing mechanism exert of internal water pressure, coupling analysis of internal water pressure exosmose in pressure tunnel and hydraulic fracturing in rock mass are summed up in this paper. It also points out the deficiencies and the aspects need to be further studied.(2)This paper put forward the cohesive crack element model which considers internal water pressure exosmose and the effect of hydraulic fracturing on the cohesive crack model in Abaqus. Also it set up the analysis model for hydraulic fracturing of pressure tunnel.(3)Research about random assignment method on cohesive crack element method considering different lining and rock parameters by random field theory is discussed in this paper.(4)This paper assumes different parameters of rock mass, lining parameters to study the influence about hydraulic fracturing. Finally we can get the influence degree of various parameters. The research can be provided as the theory reference for design and prevent of hydraulic fracturing.