Using discrete-event simulation to compare congestion management initiatives at a port terminal

This research compares the impact of infrastructure congestion management initiatives at a bulk cargo marine terminal on truck queuing and emissions. Researchers have studied the impact of individual congestion management initiatives in marine terminals extensively. However, limited research has been conducted to comparatively evaluate the impact of several initiatives. Furthermore, researchers have mainly focused on container terminals to the detriment of bulk cargo terminals even though bulk cargo marine terminals can face significant congestion challenges. A discrete-event simulation model of a bulk cargo marine terminal is developed in this research using empirical data collected from weighbridges and truck geo-positioning systems. The model is used to conduct a scenario analysis of several congestion management initiatives and assess their sensitivity to increasing terminal throughput. The performance indicators used are truck turnaround times, waiting times, turnaround time reliability, and engine idling emissions. The modelling results indicate that terminal appointment systems are one of the most effective congestion mitigation initiatives, reducing truck turnaround times by up to 65% and engine idling emissions by up to 80% compared to no intervention. The benefits accrued from terminal infrastructure expansions rival those of appointment systems only in high terminal throughput scenarios. This research contributes to the body of knowledge by presenting an approach that improves understanding of the differential impacts of congestion management initiatives on truck and environmental performance in bulk cargo marine terminals. For practitioners, this research presents congestion management considerations that balance the competitive operational, cost, and efficiency interests of individual port users with tactical and strategic concerns regarding environmental impacts.