Highly developed, European industrial countries normally have a dense network of rural highways. The future focus of roadwork in Germany, where there is a high density of 1.6 km of rural highway per km² of land, will involve upgrading and rebuilding rural highways prone to accidents. As new guidelines are not completely relevant for upgrading existing highways and exceptional permits are often required, there is an increasing need to use simulation in the design process to assess discrepancies from the standards and their effect on traffic safety. Using virtual driving (automatically using a defined driver profile or a driving simulator), it is possible to objectively assess expected driving behaviour using characteristic feature graphs and quantitative parameters derived from them. Zwickau University of Applied Sciences has developed a new multi-stage methodology for upgrading rural highways by using a 3D design working place simulator. The highway is automatically retraced using survey data and genetic algorithms in stage 1 (preliminary review) and is broken down into the horizontal and vertical projection design elements. Stage 2 involves determining the shortcomings on the road by superimposing the design elements, the actual accident figures and virtual driving runs. The actual replanning work occurs in stage 3, taking into account the minimum and maximum standard figures for the design elements. The replanning work is feasible, even if the standard figures are not met along parts of the route, but the graph figures, parameters and virtual driving runs prove that there is no reduction in traffic safety. Otherwise, the route needs to be realigned. After finishing the testing period of the hard- and software components, the methodology and the working place can be used from designing engineers for the preparing process of practical projects.

• Wolfgang Kuhn(Zwickau University of Applied Sciences, Institute of Transport and Energy Engineering)