Stability modelling of isolated rock blocks at the surface of underground excavations taking into account in-situ stresses
Résumé
Isolated rock block methods have been widely used to evaluate the stability of underground excavations in blocky rock masses. However, these methods are generally based on geometrical considerations, ignoring the underground conditions and considering simplified translational movements. This article reviews previous approaches showing their limitations then a new numerical model to analyze rigorously underground blocks is proposed. Unlike other isolated rock block methods, it integrates in-situ stresses and joints behavior. Additionally, the block is analyzed as a rigid body moving in translation and rotation. Any block geometry with multiple faces can be studied by partitioning the polygonal faces into simple elements. Finally, an application on a real case example and comparisons with other methods show the advantages of the new developed method and the effect of the parameters previously ignored.