A GRASP approach for solving the Blocks Relocation Problem with Stowage Plan

In this paper, we present a method for finding high quality solutions for the Blocks Relocation Problem with Stowage Plan (BRLP). The interest for this problem comes from the fact that previous research has shown that a significant amount of savings can be achieved, if the process of specifying the loading sequence takes into account both the state of the bay and the stowage plan. In this work, we propose a two step greedy algorithm for the BRLP. In the first one, a heuristic is used to select the next container to be loaded into the vessel. In the second step, a new heuristic is used to relocate obstructing containers. The solutions acquired in this way are improved using a correction procedure. The idea of the correction procedure is to use a heuristic approach to recognize undesirable properties of a solution and remove them. Finally, the method is extended towards the GRASP metaheuristic. Our computational experiments show that the proposed approach manages to significantly outperform existing methods for the BRLP.