Underground Excavation in Jointed Rocks

Abstract

The characteristics of unstable rock block define the magnitude of rock support and reinforcement required in the design of underground rock excavations. Variation in rock parameters may result in uncertainties on the identification of these unstable rock blocks. In view of the above, this study aims to investigate the effects of variation in rock parameters on rock block identification. Reliability-based design with probability of failure is adopted to evaluate the stability of rock block in underground excavations. The effects of scatter of various rock parameters are examined in detail using Monte Carlo simulation. Rock parameters are simulated in a systematic manner. A parametric study has been conducted and the results show that joint set concentration, ovalness and position have significant effects on the failure mode and volume of unstable rock blocks.