Multi-lane roundabouts are typically viewed by cyclists as one of the most hazardous types of intersections to negotiate and police crash statistics bear this out. For the purposes of this research, the definition of a ‘multi-lane roundabout’ is that of a roundabout that accommodates more than one lane of traffic on the circulating carriageway.
In 2003, scheme investigators in Auckland, New Zealand discovered that there is no adequate on-road design available enabling cyclists to ride through roundabouts, and this seems to be a deficiency in design standards. The purpose of this research was to come up with an on-road design that is both safe as well as attractive to cyclists. Ideally, this design will have benefits to other roundabout users as well. It was perceived that an improved design would reduce vehicle speeds and might not adversely affect junction capacity. The aim of this project was to review overseas literature and to develop a preliminary design guide.
The result of this work is the cyclist roundabout, or C-roundabout, a new concept in roundabout design.
Keywords: C-roundabout, confined geometry, cyclist, crash statistics, design, curvature, intersections, maximum path radius, multi-lane roundabout, road marking, roads, roundabout, safety, tracking curves, traffic