Optimizing open-pit mine truck dispatching through sequential mathematical programming and agent-based simulation

Open-pit mine haulage performance depends on the coordinated allocation of heterogeneous trucks and loading equipment under restricted network accessibility and uncertain operating conditions. This study develops a sequential optimization-simulation framework for evaluating truck dispatching in Mine No. ۱ of Golgohar Sirjan Company. In the first stage, a binary integer linear programming model generates a baseline dispatching schedule that maximizes transported material while considering equipment capacities, working-time limitations, continuity of loaded and empty movements, safety and queue-related restrictions, and the authorized connections between ۳۰ loading sites and four unloading destinations. In the second stage, the optimized schedule is implemented in an agent-based simulation to evaluate nine scenarios involving changes in truck availability, loading-equipment availability, and queue-formation probability. The optimized baseline schedule transported ۳۶۵,۷۹۱ tons of material through ۵,۲۹۵ haulage cycles during a ۲۲-hour operating day, corresponding to an average of ۴۰.۴۲ cycles per truck. Its ۳۶۵-day extrapolated performance exceeded the actual total material movement recorded over the reference period by ۱۰.۳۴%. Across the simulation scenarios, daily transported material ranged from ۳۷۶,۶۰۵ to ۴۳۲,۰۵۱ tons. The highest-performing scenario combined a ۱۰% improvement in both truck and loading-equipment availability with a queue-formation probability of ۰.۵۰, producing an estimated ۳۰.۳۲% improvement over actual performance. The results further show that increasing queue-formation probability consistently reduces throughput and that loading operations constitute the principal source of waiting. The proposed framework distinguishes between the planned capacity of the deterministic dispatching model and its operationally realizable performance under uncertainty, thereby providing a practical basis for coordinated fleet management and scenario-based decision support in open-pit mining.

کلیدواژه ها:

Agent-Based Simulation ، Dispatching ، Open-pit mine ، Transportation