Name: NATAN TRANCOSO GONÇALVES
Type: MSc dissertation
Publication date: 06/10/2021
Advisor:
Name |
Role |
|---|---|
| RODRIGO DE ALVARENGA ROSA | Advisor * |
Examining board:
| Name |
Role |
|---|---|
| RODRIGO DE ALVARENGA ROSA | Advisor * |
Summary: Brazil is among the largest producers in the world market of ornamental stones, and
Espírito Santo is responsible for more than 60% of the national production. More
specifically, the Port of Vitoria is the one that stands out most in the export of granite
blocks and the like. The granite blocks have different sizes and are transported in the
holds of general cargo ships, but transport costs are high. For this reason, it is
extremely important to plan the ships trips and the arrangement of the loads, in order
to reduce these costs. Aiming to assist in this planning, a mathematical model for the
integrated problem of ship routing and three-dimensional arrangement of blocks in
holds is proposed, considering the availability of different ships, multiple trips, time
windows, orthogonal rotation of blocks in three dimensions (3D rotation), unloading
sequence and the balance of ships in loading. The model seeks to minimize the costs
of ships to be chartered and the distance to sail in the planning horizon. In addition, it
minimizes total travel time and unbalanced load distribution in the bow-stern and portstarboard
directions. The model was tested with CPLEX solver. In the tests, an
exporter that charters ships under Time Charter contracts to export granite blocks from
the Port of Vitoria was considered, and the model proved to be capable of representing
the transportation planning problem in question. The results obtained showed that 3D
rotation in cargo arrangement can save a trip or even a ship. By minimizing the
imbalance in cargo distribution, completely balanced arrangements were obtained that
avoid maneuvers with water ballast to maintain the balance of ships in the loading port.
Keywords: Routing. Loading. Maritime transport. General cargo. Mathematical model.
