Geological strength index-slope: an adaptation of the geological strength index system for use in the rock slope stability assessment

The Geological Strength Index (GSI) system is the basis of parameters used in Hoek-Brown failure criterion for rock mass strength estimation. author tested this and here suggests a modified GSI called Index-slope (GSIslope). combines two different existing approaches: Slope Mass Rating (SMR). purpose GSIslope to allow engineering geologists quickly evaluate stability natural excavated slopes or open-pit mining field. computed by subtracting constant value 10 multiplication adjustment factors discontinuity orientation slope (F1, F2, F3, based on parallelism slope, dip angle, difference between inclination angle slope) from GSI, adding field groundwater rating it. Modified curves are also proposed work determine accurate ratings factors. results compared values obtained equations continuous-SMR SMR-value itself both values. comparison showed that equation valid easy use estimating factors’ value.