In locations where facilities, e. g. shopping, leisure and restaurants, are located in direct vicinity (e. g. shopping centre with gastronomic facilities) or within walking distance (e. g. supermarket and discounter, retail trade and cinema), several uses can be visited by a single person on foot. This coupling of short distances results in a lower number of motor vehicle journeys to these facilities than if the facilities were located at separate locations at a greater distance. The term "composite effect" refers to the search for several uses at one location or in its surroundings.
If new uses are favourably located in relation to transport axes (e. g. shopping facilities on a main road), new traffic is generated to a lesser extent than if the location is less favourable (e. g. away from everyday routes). The reason for this is that, in the first case, the facilities are also visited by interrupting trips/paths that have already been carried out. The driving effect describes the reduction of the number of journeys by realising chains of paths with several driving purposes, which means that new uses induce less traffic.
Take-away effects occur in all modes of transport, especially in the case of interruption of the journey from the workplace to home for shopping (e. g. visiting shops on the main road for car users, shopping at the railway station for public transport users).
In particular, multiple uses are of great importance for locations at traffic junctions. Locations in inner-city areas, at train stations and airports have relatively high composite and entrainment effects. This applies above all to the shopping area. Nevertheless, there is currently almost no knowledge of the level of the composite and entrainment effects.
The project aims at providing information on the extent of the composite and driving effects depending on the
investigated use (shopping, leisure, housing, office, community needs), the arrangement of use (associated uses such as gastronomy and leisure or unsuitable uses), the development of the uses (e. g. location on a main road or main axis of public transport) and the location of use (e. g. integrated location/on the "greenfield") which have to be included in regulations, e. g. of the for estimating the traffic volume.
In the context of value added services relevant for traffic flows, their impact on traffic, e. g. with regard to the performance of the road network and traffic connections, must usually be assessed. Users of these methods for determining traffic volumes depend on estimated values. For the main influencing factors (e. g. customers per square meter of sales area, specific number of ways per user, modal split, car occupancy) useful empirical values are usually available or these can be limited by integration of additional information available on site or plausibility considerations.