Generic form of stability charts using slide software for rock slopes based on the Hoek-Brown failure criterion

Analysis of rock slope is one of the classical problems in the field of geotechnical engineering. The stability charts are among the most convenient tools that can be used to assess the factor of safety (FOS) for rock slopes. These charts can be used for the preliminary design purposes. In this study, analysis has been performed for rock slopes with angles varying between 15 degrees and 75 degrees subjected to static and seismic loading conditions. Generalized Hoek-Brown strength criteria have been used to simulate the stress-strain behavior of rock material. The height of the rock slope is kept fixed (27 m) and the strength parameters are varied to evaluate the FOS values. The stability charts are prepared between the FOS and a dimensionless parameter (gamma H) over bar, and presented in a generic form where transformed stresses have been used. Expressing the major and minor principal stress components obtained from triaxial test in the transformed state greatly helps in reducing the dispersion of the data, and therefore generic expression of stability charts built using the transformed stress components can be advantageous. It is observed that for different slope angle, the FOS values decline as the value of (gamma H) over bar increases and vice versa. It is further observed that at lower inclination of slopes, the mode of failure conforms to base failure, but at higher inclination angle, the mode of failure changes to toe failure.