Numerical Assessment of Factor B in Mathews ’ Method for Open Stope Design

A numerical modelling study was completed to derive the Factor B curves proposed by Mathews et al. (1980) & Potvin et al. (1988) to further understand the relationship between joint orientation and stope stability. A continuum finite element modelling approach which included joint elements was adopted to back-analyse and assess the influence of various joint properties and stress states on the shape of the Factor B curve. This paper provides insight into mechanisms affecting the shape of the Factor B curve. A better understanding of factors controlling the B-value potentially reduces some of the conservatism in the design of open stopes and other underground excavations. ROCKENG09: Proceedings of the 3rd CANUS Rock Mechanics Symposium, Toronto, May 2009 (Ed: M.Diederichs and G.Grasselli)