Minimization of overstowage in containership operations

Overstowage is a situation arising in stacking operations when the storing and retrieval sequences do not obey the ‘last-in first-out’ rule. This paper models overstowage as it appears in containership operations by taking into account placement constraints, specifically, stability requirements of the vessel. The latter translates into a constraint on the vertical center of weight of the containers. A polynomial-time recursive algorithm is developed for the one-stack case. Features of multistack problems are presented.