摘要：AbstractThe paper presents a critical review of the Australasian, EU and US roundabout geometric design standards and guidelines and identifies inconsistencies of the Italian roundabout standard which deserve improvement. As a result, recommendations for improvement of the Italian standard are proposed. These recommendations are mainly based on the concepts of design flexibility and performance based design. Indeed, rigid standards which do not really take into account safety and operational consequences of the design decisions and the need to balance opposite demands might produce undesirable outcomes.
