Road infrastructure presents many significant ways of dealing with the problem of road safety. One of the aims of research work carried out by INRETS in the past few years has been to attempt to reveal the impact of defects and defect combinations on road accidents in the open country. The method used for this work is original in that it makes use of measurements obtained using high-speed pavement surveying devices as in intermediate safety indicator. The results of this work have made it possible to pinpoint a certain number of thresholds (radius of curvature, evenness, skid-resistance and sight-distance) beyond which dysfunctions may become apparent on either the driver or the vehicle. The survey described in this paper was carried out on a sample of first class secondary roads in the Bouches du Rhône (France), and was done in two stages: (a) development of a secondary road typology using infrastructure characteristics and traffic flow (finding analogies with the national network), and (b) study of the similarities in accident mechanism between main road routes and secondary road routes of the same type. The results show that it is possible to use safety diagnostic methodologies based on high-speed measuring devices to study certain first class secondary roads. The benefit gained by such surveys is that of being able to propose documents which will provide the public authorities responsible for secondary roads, with a better knowledge of the way in which their road network functions, and in this way make advances in the field of road safety.
Abstract