Production scheduling is often reliant on an estimation of a mine's trucking capacity. While this mechanistic approach is relatively simple, it often over-estimates actual throughput resulting in under-utilisation of downstream process and a shortfall in revenue._x000D_
An alternate approach has been developed that recognises the interdependency between processes in the mine production system including materials loading, haulage and crushing. This approach incorporates a heuristic model based on queuing theory that accounts for the variability in performance of individual processes and that this paper presents the results of a study comparing the conventional approach to mine scheduling with a capacity constrained model at a large open cut mine having a truck and shovel fleet. The capacity constrained model consistently predicted a lower material throughput compared to the conventional approach. Differences in throughput between the two approaches were found to increase with loading time, for example when loading time exceeded 3.9 minutes there was a shortfall of up to 40 per cent in estimated throughput. Longer travel times tended to ameliorate any differences. When applied to a mine schedule that extended over a two and a half year period, the difference was equivalent to a shortfall of nearly eight per cent in total material movement._x000D_
FORMAL CITATION:Najor, J and Hagan, P C, 2007. Improvements in truck and shovel scheduling based on capacity constraint modelling, in Proceedings Sixth Large Open Pit Mining Conference 2007, pp 87-92 (The Australasian Institute of Mining and Metallurgy: Melbourne).