Study Details

Study Title: Injury crashes with bicyclists at roundabouts: influence of some location characteristics and the design of cycle facilities

Authors: Daniels et al.

Publication Date: APR, 2009

Abstract: Problem Previous research indicated that conversions of intersections into roundabouts appear to increase the number of injury crashes with bicyclists. However, it was assumed that the effectiveness of roundabouts could vary according to some differences in design types of cycle, facilities and other geometrical factors. Method Regression analyses on effectiveness-indices resulting from a before-and-after study of injury crashes with bicyclists at 90 roundabouts in Flanders, Belgium. Results Regarding all injury crashes with bicyclists, roundabouts with cycle lanes appear to perform significantly worse compared to three other design types (mixed traffic, separate cycle paths, and grade-separated cycle paths). Nevertheless, an increase of the severest crashes was noticed, regardless of the design type of the cycle facilities. Roundabouts that are replacing signal-controlled intersections seem to have had a worse evolution compared to roundabouts on other types of intersections. Impact on industry The results might affect design guidelines for roundabouts, particularly for the accommodation of bicyclists.

Study Citation: Daniels, S., Brijs, T., Nuyts, E., Wets, G. "Injury crashes with bicyclists at roundabouts: influence of some location characteristics and the design of cycle facilities." Journal of Safety Research. Vol. 40, Issue 2, pp. 141-148. (2009)


CMFs Associated With This Study

Category: Bicyclists

Countermeasure: Replacement of traditional intersection with roundabout with a grade separated cycle path

CMF CRF(%) Quality Crash Type Crash Severity Roadway Type Area Type
0.56 44 3 Stars Vehicle/bicycle All Not Specified Urban
1.31 -31 2 Stars Vehicle/bicycle K,A Not Specified Urban

Countermeasure: Replacement of traditional intersection with roundabout with cycle lanes

CMF CRF(%) Quality Crash Type Crash Severity Roadway Type Area Type
1.93 -93 3 Stars Vehicle/bicycle All Not Specified Urban
1.37 -37 2 Stars Vehicle/bicycle K,A Not Specified Urban

Countermeasure: Replacement of traditional intersection with roundabout with separated cycle path

CMF CRF(%) Quality Crash Type Crash Severity Roadway Type Area Type
0.83 17 3 Stars Vehicle/bicycle All Not Specified Urban
1.42 -42 2 Stars Vehicle/bicycle K,A Not Specified Urban