Lifetime-Oriented Structural Design Concepts- P4: At the beginning of 1996, the Cooperative Research Center SFB 398 financially supported by the German Science Foundation (DFG) was started at Ruhr-University Bochum (RUB). A scientists group representing the fields of structural engineering, structural mechanics, soil mechanics, material science, and numerical mathematics introduced a research program on “lifetimeoriented design concepts on the basis of damage and deterioration aspects”. | Transport and Mobility 47 information about the influence of the dynamic behaviour of the vehicles and the bridge structures including information about the pavement quality information about the different types of bridge structures and the corresponding influence surfaces principles for the model calibration for ultimate limit and fatigue limit states and the damage accumulation under consideration of different materials methods for the exploitation of the currently available traffic data development of large capacity and heavy load transports not covered by the normal traffic models the influence of future political decisions with regard to new traffic concepts. Basic European Traffic Data With regard to the cross border trade load models must be based on traffic data which are representative for the European traffic. For example the development of the models in Eurocode 1-2 9 is based on data collected from 1977 to 1990 in several European countries 487 720 530 37 157 361 158 . The main data basis with information about the axle weights of heavy vehicles about the spacing between axles and between vehicles and about the length of the vehicles came from France Germany Italy United Kingdom and Spain. Most of the data relate to the slow lane of motorways and main roads and the duration of records varied from a few hours to more than 800 hours. Another important point is the medium flow of heavy vehicles per day on the slow lane. In order to analyse the composition of the traffic for the development of the load model in 9 four types of vehicles were defined for the European load model for bridges. Type 1 is a double-axle vehicle Type 2 covers rigid vehicles with more than two axles Type 3 articulated vehicles and Type 4 draw bar vehicles. Figure shows the typical frequency distribution of these four types resulting from traffic records of the Auxerre traffic in France. The data base of different countries shows that the traffic composition is not .
