BRITO, L. G. S.; BRITO, Luiz Gonzaga Silva de.
Résumé:
The purpose of this research is to estimate the productivity of an underground mine
haulage system, using the simulation technique. A hybrid model involving deterrninistic
and stochastic simulation has been employed. The model attempts to represent as much as
possible the real system. The model has been validated by means of comparison between
the simulation results and historical data obtained from Mmeracfio Vale do Jacurici,
Ipueira Mine, located in the State of Bahia.
The model is based on the advance-clock technique making possible to take into account
the mterference between equipaments at the intersection points of the haulage network.
The deterrninistic simulation allows the calculation of the travel times, while the stochastic
simulation evaluates the efficiency of the haulage system. The computer program takes
into account the relevant variables cjccurring in the day-to-day mine operation, such as
elapsed time for change of shifts, time off for meals, equipment breakdown, traffic jam at
loading and dumping points, waiting time at road crossings, etc.
As much as 5,000 simulation runs have been performed in order to ensure a statistical
representation of high degree of confidence. The variables considered for estimating the
productivity of the system have been the availability of equipment and the existence of rock
blocks at the loading points. The variables related to the haulage distance and the number
of LHD's per advancing feces have also been considered. The results from the model
showed a good agreement with the data from the real system, indicating that the variability
between the actual and the simulated system is about 5 percent. The model does not
optimize the system in a global way, but it yields good results most of the time.
