Experimental study on mechanical and nonlinear seepage of single rock mass fracture with shear failure
The stability of fractured rock mass is important for the operation of reservoir and dam system under complex stress and seepage condition.In order to clarify the fracture mechanics and seepage charac-teristics of rock mass with shear-seepage coupling,the shear-seepage coupling tests of single fracture were carried out by making rock-like specimens.The evolution law of the key parameters,including shear strength,increment of normal displacement,dilatancy angle and parameters of FORCHHEIMER's law,was analyzed;the peak shear displacement was set as the dividing point.The total shear strength calculation e-quation was established based on the PATTON's and proposed dilatancy equations.FORCHHEIMER's law was used to analyze the non-linear seepage characteristics of fracture,the evolution law of the linear and nonlinear term coefficients of FORCHHEIMER's was revealed,and the computational formula of critical Reynold's number was proposed to determine the seepage flow regime.The results show that the filling pro-duced by shear failure has an obvious effect on the shear strength,dilatancy angle and non-linear seepage characteristics of fracture.The established shear strength and dilatancy equations can confirm the shear strength and aperture of fracture at any time.Due to the influence of inertia force,the nonlinear seepage characteristics of fracture under high hydraulic pressure are significant.The values of two coefficients of FORCHHEIMER's are decreased and Reynold's number is increased with increased shear displacement.
single fractureshear-seepage couplingshear strengthshear failurenon-linear seepage
万方数据
维普
