Did commercial traffic models already reach adulthood?

Abstract

Commercial transport is expected to augment over the coming years. The road will remain the dominating mode of landside transport and congestion seems to be likely to become a common status on the major European motorways. At the same time the capacity and performance of rail and inland waterways does not match the needs of shippers for many kinds of goods and traffic relations. In order to evaluate possible measures that render smoothly operating traffic feasible, models are a valid tool for testing scenarios. Currently existing “standard travel demand models” tend to refer to passenger transportation though. With its high complexity of transport devices – ranging from van to truck, from vessel to aircraft and also including rail traffic –, its multiple players and decision makers (e.g. drivers, shift managers, traffic controllers) as well as its international routings, these standard travel demand models are not able to reflect the system of commercial transport to its full extend. It is therefore the purpose of this article to reflect the current status of commercial traffic modelling and to indicate possible directions for its future development. Furthermore, it is evaluated which requirements must be met by a commercial traffic model in order to provide for valuable findings, which than can contribute towards the development of sustainable transport concepts. Commercial traffic can be divided into freight traffic and service oriented traffic. The former can be found on all local scales, while the latter is particularly relevant for metropolitan traffic. The challenge of commercial transport modelling is therefore twofold: the decision processes of the actors are complex, and little data is freely or easily available to describe these decision processes. Furthermore private traffic must be considered in the route assignment because of reflecting the entire traffic flow and the valid calculation of travel times and transport costs. The article expands upon these challenges to commercial transport modelling with a special focus on large-scale freight models. Based on the findings from this systematic analysis it is mapped out in a second step, which developments are still needed to cover the short-comings of currently existing models in regards to pan-European commercial transport modelling: In commercial transport a small number of actors commonly has a big impact on the traffic. It is difficult to define homogenous groups which are required for macroscopic modelling. The success of microscopic modelling, on the other hand, depends on detailed data on and understanding of motivations behind the actions of the diverse actors in commercial transport. It is apparent that commercial traffic modelling is far from reaching its adulthood, adolescence is just about to begin. The major issue has to be seen in data availability and data quality. This challenge calls for modelling approaches which make best use of the available data. It is, however, also clear that models based on the currently available data are limited either in scope or reliability.