A heuristic procedure for the outbound container space assignment problem for small and midsize maritime terminals

The space allocation problem for outbound containers involves assigning containers to specific locations in the yard as they are delivered to the port. The problem is challenging because the arrival sequence is not known in advance, which makes it difficult to minimize container rehandling during the ship loading operation. This paper provides a heuristic procedure for the container space allocation problem employing reach stacker vehicles as container handling equipment. Procedures reported in the existing literature apply to rubber-tired gantry (RTG) cranes. Therefore, we are extending current research to the cases of port terminals that employ reach stacker vehicles, commonly used by small or medium size ports in emerging countries such as in Latin America. In addition, we adapted a procedure recently published in the literature. Empirical results show that the proposed heuristic yields better performance than the adapted heuristic. Another contribution of this paper is the formulation of a perfect information mathematical model which computes a lower bound on the number of rehandles required to load a group of containers given their arrival sequence to the port. The gap between the number of rehandle movements achieved by the proposed heuristic and the perfect information model is reported.