Non-linear shear strength reduction technique in slope stability calculation

To exactly implement the non-linear Hoek-Brown shear strength reduction in slope stability calculations, three aspects of the problem are considered. Firstly, the normal and shear stress relationship of the generalized Hoek-Brown criterion (2002 edition) is derived by introducing the Mohr-Coulomb instantaneous friction angle as a variable. Secondly, the instantaneous Mohr-Coulomb friction angle and cohesive strength are derived for a micro-unit at a given stress state and they can be used to describe the shear strength of the rock mass under different stress states. Finally, the implementation of the non-linear shear strength reduction is described and a slope example is selected to verify our method. This technique can be also applied to other non-linear failure criteria. (C) 2009 Elsevier Ltd. All rights reserved.