Moving from Conventional Roundabouts to Turbo-roundabouts

This paper introduces the turbo-roundabout concept and compares its performance with the conventional double-lane roundabout in terms of safety and capacity. While researchers agree as to the safety benefits of turbo-roundabouts, improvement in terms of capacity is still open to discussion. The application of a new calculation method shows that only in very specific and rare cases of traffic demand, can a turbo-roundabout be expected to provide more capacity than a double- lane conventional roundabout of similar size.