Risk Analysis for Rock Slopes in Open Pit Mines. Part V. Probablistic Models of Jointed Rock Mass Deformation and Their Implications.
Einstein-HH; Baecher-GB; Veneziano-D; Et Al
NTIS: PB/81-201634 :113 pages
Rock mass deformability is commonly predicted using correlations with rqd or other indices of rock mass quality or by extrapolation from large in situ tests. Based on the probabilistic description of rock masses empirically developed, a new approach was attempted in modeling for predictions of deformability. This approach decomposes the rock mass into spatially variable joints described by probability distributions and intact rock blocks. Stiffnesses and elastic parameters are associated with the joints and intact blocks and deformations are built up by adding the contributions of each. This allows relaxation of many of the simplistic geometric assumptions that constrain parallel attempts to model deformation in rock masses. The model has been applied to four standard cases to test its results against previously existing models and to check whether it replicates empirical correlations. When joints are taken as parallel, common empirical correlations are closely approximated by the model output. However, the closeness to empirical correlation breaks down when variability of the jointing geometry is increased.
CP; Final Contract Report;
NTIS Accession No.
Massachusetts Inst. of Tech.