Integrated Optimization of Shut-Outs Clearance and Pre-marshalling Considering the Ship’s Stowage Plan in a Container Terminal

In container terminals, the existence of blocking containers and shut-out containers not only affects the efficiency of loading operations, but also consumes a large amount of yard cranes and internal trucks. This paper optimizes the integrated operation of shut-outs clearance and pre-marshalling in a block, taking into account the re-establishment of the ship’s stowage plan. We consider the realistic constraints such as the waiting time of the internal truck, the yard crane scheduling and the amount of relocation, and construct a mixed-integer optimization model with the objective of minimizing the longest completion time of the yard cranes. The GAALNS algorithm, which combines the genetic algorithm and adaptive large neighborhood search algorithm, is designed to solve the model. The proposed model solves the scheduling problem for both the internal truck and the yard crane and gives the optimal order of operations for each yard crane and truck. Comparing the solution results of GAALNS and CPLEX, the difference between them is within 5%. GAALNS algorithm solving is not only fast, but also can solve large-scale cases. Numerical experiments verify the effectiveness of the model and algorithm. Through the comparative analysis with the existing strategies, we give the advantages, disadvantages, and adaptation scenarios of each scheme, which provide insights for the management and operation of container terminals.