International Comparison of Roundabout Design Guidelines

Roundabouts have been a key form of junction in the UK for many years. They are used on all classes of road in both urban and rural areas for the efficient and safe control of traffic, particularly where side road flows are high. Roundabouts are the most common type of control used at motorway intersections, and are heavily used throughout the UK's trunk and principal road network, as well as on local authority roads. The paper describes a state-of-the-art review of roundabout design intended to lead to a revised UK Design Standard to meet the needs of modern roads. The need for a hierarchical approach is considered, the intention being to place much greater emphasis on the interests of vulnerable road users. Concerns relating to the current Standard are discussed, including the problem of large vehicle rollover accidents.