Numerical simulation analysis on strength reduction for slope of jointed rock masses based on gereralized Hoek-Brown failure criterion

As a semi-empirical rule for estimating shear strength of integral rock or joint rock masses,the Hoek-Brown failure criterion has been one of the most useful criteria in forecast and calculation of rock masses strength.Moreover,it has widely applied in calculation of slope limit equilibrium,but rarely used in numerical simulation calculation.Numerical simulation model was established based on the gereralized Hoek-Brown failure criterion,and the factor of safety slope was calculated based on the strength reduction method.Compared with the numerical simulation of equivalent Mohr-Coulomb failure criterion and the calculation of the limit equilibrium,it was concluded that the calculated results based on Hoek-Brown failure criterion were similar to those calculated by other methods and because of different flow rules were used in different failure criteria,the position of the sliding surface and the deformation characteristics had some difference under different failure criteria.Compared with the Mohr-Coulomb failure criterion,gereralized Hoek-Brown failure criterion could more properly exhibit the deformation and failure characteristics of jointed rock masses as it used plastic flow rule based on stress level.Hoek-Brown failure criteria could effectively reflect the nonlinear failure characteristics of rock masses,and it made the calculated results closer to practical situation.