Abstract
This paper concerns the problem of operating a landside container
exchange area that is serviced by multiple semi-automated rail mounted gantry cranes
(RMGs) that are moving on a single bi-directional traveling lane. Such a facility is
being built by Patrick Corporation at the Port Botany terminal in Sydney. The gantry
cranes are a scarce resource and handle the bulk of container movements. Thus, they
require a sophisticated analysis to achieve near optimal utilization.We present a threestage
algorithm to manage the container exchange facility, including the scheduling
of cranes, the control of associated short-term container stacking, and the allocation
of delivery locations for trucks and other container transporters. The key components
of our approach are a time scale decomposition, whereby an integer program controls
decisions across a long time horizon to produce a balanced plan that is fed to a series of
short time scale online subproblems, and a highly efficient space-time divisioning of
short-term storage areas. A computational evaluation shows that our heuristic can find
effective solutions for the planning problem; on real-world data it yields a solution at
most 8% above a lower bound on optimal RMG utilization.