PDPTW: a case study of a container transportation company

In logistics and transportation many routing problems can be defined as pickup and delivery problems with time windows. In the present paper, one particular case is introduced in which a small fixed fleet of container barges needs to be routed on inland waterways. In contrast to the Liner Shipping problem, barges do not sail on a fixed schedule. Instead, a sched- ule is composed by considering the pickup and delivery intervals of all incoming orders within the planning horizon. Containers can be stacked in two or three layers, while the number of layers and the total container weight determine the barge’s draft and thus the possibility to sail beneath bridges. Exchanging barges between towboats enables variability in barge capacity and therefore assists in generating cost-efficient routes. Addition- ally, the operator’s inland location imposes extra constraints concerning lock waiting times and varying travel times. The operator’s main goal is to offer high quality services with competitive costs in comparison with truck haulage. When the fleet capacity is insufficient for delivering all or- ders within the planning horizon, alternative means of transportation (i.e. truck haulage, leasing an extra barge) are necessary. However, these are more costly and are penalized accordingly. Real world data was provided by the container transportation company BCTN Meerhout. We present a heuristic approach to this problem. The optimization method is evaluated on the real data and experiments reveal competitive costs.status: publishe