A Mathematical Model for the Container Stowage and Ship Routing Problem

The main goal of this paper is to present a mathematical model for a fleet of containerships with no pre-defined routes, considering demands and delivery deadlines and overstowing prevention. The objective is to minimize the total distribution cost in the contest of the short sea shipping. The short sea shipping is a very complex problem that belongs to the class of routing problems, more precisely, to the Capacitated Vehicle Routing Problem with deadlines and loading constraints. In this problem two major decisions must be made: which ports should be visited by each vessel and the related visit sequence, and where to load the containers in vessels in order to prevent overstowing. A mixed integer programming model for the problem is presented and solved. This mathematical formulation intends to contribute to a better management of small fleets of containerships in order to reduce transportation time and delivering costs.