The study is carried out within the framework of a reformulation of the freight transport policy in Brussels. The aims of the study are to draw up a diagnosis of the present impacts of freight transport on the environment in Brussels, to identify the trends and to elaborate a global strategy to cope with the results of the diagnosis. The first question to be answered by the paper is to quantify the present impacts of freight transport on urban traffic. The main tool designed to answer this question is an urban traffic model simulating freight transport together with passenger trips in order to evaluate their non linear impacts on the general traffic conditions. The following procedure was followed: (1) modelling the demand generated by the private cars and the vans, the demand generated by the light lorries and the heavy lorries (2 user class); (2) assign, on a model of the road network, the total demand and calculate indicators of the present situation (total travelling time, total travelling length, total fuel consumption, average speed, traffic noise and pollutant emissions...); (3) assign on the same network model the demand generated by the private cars and the vans only and calculate the same indicators; and (4) analyse the difference in the indicators values between the two assignments as the impacts of the lorries traffic.
Abstract