Prediction of failure mode in weak rock slopes using fuzzy slope mass rating

YARDIMCI A. G. , Karpuz C.

14th International Congress on Rock Mechanics and Rock Engineering, ISRM 2019, Foz do Iguaçu, Brazil, 13 - 18 September 2019, pp.3667-3673 identifier

  • Publication Type: Conference Paper / Full Text
  • Volume:
  • City: Foz do Iguaçu
  • Country: Brazil
  • Page Numbers: pp.3667-3673


© 2020 ISRM.Stability of weak rock slopes are threatened by structurally controlled mechanisms or mass failure. Shallow depth lignite beds are commonly exploited by surface mining. Preliminary slope stability analysis is carried out by practical tools that perform quick stability investigation with limited data. Kinematical analysis is a widely used method that requires orientational data and the rock mass friction angle. However, geological or mechanical features of the rock mass are disregarded. Slope Mass Rating (SMR) is an alternative that considers the basic Rock Mass Rating (RMR) parameters and the discontinuity orientations. However, it suffers from the common drawbacks of classification systems. In addition, it is required to be tuned for weak rock mass. This study modifies the classical SMR system by Fuzzy Logic to predict the slope failure mode. Enhancements on the prediction mechanism depend on the expert opinion. Fuzzy membership functions and rules were outlined by the expert view. The fuzzy interpretation mechanism was established. Later, the modified methodology was validated on two large slope failures of surface lignite mines in Turkey. Other failure modes were investigated by 3D discontinuum numerical simulations. The modified methodology presented in this study enhances the prediction capability of SMR with no claim to replace the analytical or numerical solutions.