Estimating the rock mass deformation modulus: A comparative study of empirical methods based on 48 rock mass scenarios

The rock mass deformation modulus, Erm, is an input parameter for most numerical modeling to verify the behavior of rocks due engineering activities within/on it. Among common methodologies used estimating this parameter, empirical correlations based on classification schemes (e.g., RQD, RMR, GSI, and Q) stand out most, principally because their low cost when compared other methods. Herein, main in practice are evaluated comparted 48 different quality scenarios, previously characterized classified according systems. results obtained by each demonstrated that normalized correlations, is, ratio intact Erm/Ei, underestimate Erm values those from not-normalized scenarios better masses. For poor both non-normalized correlation presented similar results. proposed Hoek Diederichs (2006) Galera et al. (2007) estimated more central all while Mitri (1994) Sonmez methods high respectively.