In Germany accident remedial work at high risk sites (HRS) is normally based on the knowledge and experience of the involved engineer. There is no systematic approach to find the optimal measure to improve the road safety at a certain site. Accident data from 140 urban sites, which were identified as HRS and were treated with different kinds of remedial measures, were collected and analysed. In addition all available information about these sites (like aspects of design and control) were collected from the responsible authorities. For every site the effectiveness of the applied measure is investigated in great detail. All different actions being taken are compared regarding several aspects of the measure itself, measure itself, the site and the accident situation, in order to find out which approach is more suitable in a certain case than another. As a result a classification of accident remedial method and type of intersection is formulated. This should give easy to understand instructions for the practising engineer or police officer to find out suitable methods to improve safety urban HRS. In the final step the results are used to create an expert system that can give well structured recommendations at remedial measures suitable for the individual sites. (A)
Abstract