The estimation of rock mass strength properties using probabilistic approaches and quantified GSI chart

The strength and deformability properties of rock mass are required in many mining and civil engineering projects. As rock masses have a complex and uncertain nature, to deal with such complexity the use of probabilistic approaches seems to be more appropriate than the use of conventional deterministic approaches. In this paper, a recently presented quantitative approach was combined with the probabilistic approach to determine GSI value and predict rock mass strength and deformability parameters. Using the estimated GSI and measured intact rock properties the probability density distributions of rock mass strength and deformability properties were calculated through a Monte Carlo method. A comprehensive database is constructed using the information from the drill holes in the mine located in the Eastern part of Turkey. By means of the presented methodology a wide array of strength and deformability parameters to be used in any preliminary design studies were obtained.