Rock Slope Analysis with Nonlinear Hoek-Brown Criterion Incorporating Equivalent Mohr-Coulomb Parameters

In the present work, the results of rock slope analyses incorporating nonlinear Hoek-Brown yield criterion with equivalent Mohr-Coulomb strength parameters to simulate rock mass behaviour are presented. The factor of safety (FOS) of rock slopes are calculated using Morgenstern-Price and Spencer's method. A simplified method of generating non-circular segmented failure surface is proposed. The search of minimum FOS and associated critical non-circular failure mass for rock slopes is performed by Particle swarm optimization (PSO) technique. A MATLAB code is developed incorporating nonlinear Hoek-Brown criteria with equivalent Mohr-Coulomb strength parameters and coupled with PSO to analyze stability of rock slopes. The efficiency and accuracy of the developed MATLAB code is established by comparing the obtained results with those from existing literatures. Furthermore, the analyses of slopes are performed with varying height and slope angle for an intact rock slope with varying material parameters such as Hoek-Brown constant mi and uniaxial compressive strength sigma ci for rock material. It is found that the FOS value follows a decreasing pattern if height and the slope angles are increased.