The Hoek-Brown Failure Criterion

Abstract

One of the most challenging problems encountered in the design of rock engineering projects is the estimation of strength and deformation properties of rock masses containing joints, bedding planes, and other geotechnical defects. Currently, one of the commonly used empirical failure criteria in rock engineering is the Hoek-Brown (HB) failure criterion. The main breakthrough of the HB criterion is that it opened up for empirically estimating rock mass strength and deformation properties at the engineering scale. The HB criterion started with intact rock properties and then it was extended to estimate the rock mass strength by using the Geological Strength Index (GSI) and the disturbance factor D to reduce intact rock properties. A number of empirical models have been proposed in parallel with the HB failure criterion to estimate the rock masses properties such as deformation modulus, UCS and shear strength parameters.