ABSTRACT

The design of an optimum open pit requires an estimate of a set of average and safe slope angles. Pit slope angles may vary throughout a deposit to accommodate varying rock characteristics and ore/waste ratios. This paper describes two approaches and associated computer programs for the estimation of a set of safe average pit slopes for use in an optimal pit design program. The first approach determines the steepest safe angle by kinematic analysis. The second approach includes methods for the design of slopes by limit equilibrium analysis in terms of the safety factor or the probability of failure using the Monte Carlo simulation technique.