Three-dimensional stowage optimization of general cargo ships considering stevedoring complexity in multiple ports

Abstract

In the stowage optimization problem of general cargo ships loading in one port and unloading in multiple ports, only thinking over the maximum total loading volume may lead to higher stevedoring complexity. In addition, the two-dimensional cargo ship stowage diagram is difficult to describe the loading rules and stevedoring complexity of stacked general cargoes. In this paper, by means of three-dimensional stowage, an algorithm for calculating the sum number of the reloading operations of the general cargo ship during unloading in multiple ports is proposed. The optimization objective is to maximize the total volume of cargo hold loading and minimize the sum number of the reloading operations of the cargo hold during unloading in each port. A three-dimensional stowage optimization model of a general cargo ship is established by combining the general cargo loading sequence with the loading optimization rules. A genetic algorithm improved on mutation operator solves the model by coordinating and optimizing the general cargo loading sequence. Through example verification, the model can obtain a general cargo ship stowage plan that satisfies the large total volume of loading and the insignificant sum number of the reloading operations during unloading, proving the algorithm model's effectiveness.