A brief outline of the development of ARCADY and PICADY, the British junction design programs for roundabouts and priority junctions, is given. Empirical relationships linking injury accidents at junctions to the geometric layout have been developed and are discussed.The case of rural 'T'-junctions is used to present the methodology used in the analysis. Road accident costs in Great Britain exceeded 6000m in 1989. Over half of road accidents occur at or near junctions. TRRL has estimated that the use of these safety relationships could reduce junction accidents by up to 30% at junctions with particularly bad records.
Samenvatting