Numerical modelling of block size effects and influence of joint properties in multiply jointed rock

Two dimensional numerical experiments are conducted for investigating the effects of block size and joint properties on the behaviour of multiply jointed rock. The paper explains how the size of the individual blocks controls both the shear strength of the assembly (rock mass) and its deformational characteristics. A closely jointed rock mass, in which block rotations occur, exhibits a lower stiffness but a higher strength than. a rock mass with widely spaced joints. These numerical results are similar to those from reported physical model tests on jointed slabs of a rock model material. The paper shows how parametric studies on a single joint using the Barton-Bandis (BE) formulation are useful for providing information about the response of a jointed rock mass. (C) 1997 Elsevier Science Ltd.