Simulation of truck-traffic to the Harbour of Copenhagen

In connection with the work 'Environmental impacts of freight transport by truck and ship - A pilot project for the Copenhagen Metropolitan area' done by Copenhagen Business University, Otto Anker Nielsen was hired to do a simulation of the distribution and routes of truck-traffic on the road network in Copenhagen. Truck flows were investigated within 3 categories to- and from Copenhagen: International traffic, traffic to- and from the harbour and national traffic. Traffic surveys delivered by the Business Univ. were split up in a more detailed level by a sketch method. Hereafter the traffic was assigned onto a road network earlier implemented at IFP by a probit-based route choice model. Beside the practical part of the work, the study gave some interesting insight to truck driver's route choices:
1. Truck drivers have a less stochastic behaviour than personal car drivers.
2. Truck drivers have a large preference for big roads (especially motorways) and little preference for small roads. Thus, weighted speeds (perceived costs) can advantiously be used in the model in stead of the real speeds. In addition the preference seems to be better described by using travel time rather than travel cost (or length) as explanatory variable.
3. It is less important to use a traffic dependent model (User Equilibrium) than for personal car traffic (under the premise that the traffic network is medium loaded as in Copenhagen).