ACCIDENT ANALYSIS OF TWO-LANE MAIN ROADS WITH A SPEED LIMIT OF 90 KM/H

This report is a study of connections between: (1) paved width and traffic safety; (2) accident rate and traffic flow; (3) single and multi-vehicle accidents and traffic flow, paved width, alignment and region; (4) injury consequence (number of injured or killed per accident) and injury rate (number of injured or killed per vehicle mileage) and various road and traffic factors. Furthermore variations in accident costs are studied. There is a strong connection between accident rate and paved width, but it is not established that the accident rate is lower for a paved width of 12,7 M than for a width of 10,8 to 12,7 M. The relation between accident rate and adt is weak. As to the injury consequence, a correlation was established with the respective region, while a correlation was established with paved width and alignment as to the injury rate. Taking only single-vehicle and multi-vehicle accidents into account, no differences were found in the cost-of-accident index for different paved widths, alignments or traffic flows. However, basing the cost-of-accident index on all types of accidents, the cost-of-accident index will vary chiefly according to traffic flow and paved width. /TRRL/