The paper describes the result of a comprehensive study of traffic accidents at grade-separated intersections in Norway. The study is based on traffic accident data from 110 Norwegian intersections during the period 1990 - 1994, and is a further development of the results from a Master thesis study. Accident data and accident rates are presented on a macro level (different intersection types) and on a micro level (separate analysis for each typical intersection element). Intersection types covered by the macro study are the so-called Half-cloverleaf intersections, Diamond intersections, Trumpet intersections and combinations of main intersection types. On the micro level accident rates are found for different typical intersection elements like exits from the primary road (parallel, direct, T-junction), entries to the primary road (parallel, direct, T-junction), off-ramps, on-ramps, connections between ramps and the secondary road (T-junctions, X-junctions, roundabouts, traffic signals) and secondary and primary road elements. Some practical applications of the results are presented and discussed. (Author/publisher)
Abstract