Sixty-one rural multi-lane intersections throughout Indiana were studied. Thirty-nine intersections were randomly selected from all such intersections in the state and twenty-two were submitted by the Indiana State Highway Commission. Geometric, accident and traffic volume data were collected from each intersection. The average rural multi-lane highway intersection had four times the number of accidents than the average rural intersection. The following findings were made about the randomly selected rural multi-lane highway intersections: unsignalized intersections were found to have a lower accident rate, median barriers and large intersections were found to increase the accident rate, and as the size of stop sign on the minor road increased, accidents decreased. The following findings are applicable to high accident signalized multi-lane intersections: the presence of stop line pavement markings decreased the accident rate; route markers and/or signal ahead advance warning signs on the minor road reduced the right angle accident rate; and a horizontal curve on the major road and/or a skew of the two roadways were found to increase the accident rate considerably. (FHWA).
Abstract