Eriang loading models in earthmoving

Abstract

Abstract A straightforward approach is presented for the productivity calculations in shovel-truck type operations applicable to earthmoving, quarrying, and open cut mining. The approach is based on finite source queueing models where the loading times of the shovel are modelled as Eriang distributions and the truck backcycle times follow exponential assumptions. The state of the system is defined as the number of Eriang phases left in the system and yet to be processed; this requires keeping track of which phases the trucks are in. The balance equations for such queueing models are derived and a sequential calculation procedure requiring minimal computational effort is put forward by which the shovel utilization and hence the operation productivity may be calculated. Example calculations, together with a field study illustrating the applicability of the queueing models, are also presented.