Roundabout Design Practices: International Overview and Insights to Update the Italian Standard

The use of roundabouts improves intersection safety by eliminating or altering conflict types, reducing crash severity, and causing drivers to reduce speeds. However, previous studies have showed that poor geometric design can be a major contributory factor in crashes at roundabouts. Poor geometric design can result from inconsistencies in geometric design standard or the lack of standards. With the growing number of roundabouts internationally, several countries have recently updated their standards and guidelines. A review of the Australasian, EU and US standards and guidelines showed several inconsistencies within the Italian roundabout standard (and the standards used by other countries). Several recommendations for improvement of the Italian standard have been 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 opposing demands might produce undesirable outcomes. Finally, the authors would like to highlight the need for further research on the relationships between roundabout geometric design criteria, drivers’ behavior and safety.

• Supplemental Notes:
  • This paper was sponsored by TRB committee ANB75 Roundabouts.
• Corporate Authors:

  Transportation Research Board

  500 Fifth Street, NW
  Washington, DC  United States  20001
• Authors:
  • Montella, Alfonso
  • Turner, Shane
  • Chiaradonna, Salvatore
  • Aldridge, Dave
• Conference:
  • Transportation Research Board 92nd Annual Meeting
  • Location: Washington DC, United States
  • Date: 2013-1-13 to 2013-1-17
• Date: 2013

Language

• English

Media Info

• Media Type: Digital/other
• Features: References; Tables;
• Pagination: 20p
• Monograph Title: TRB 92nd Annual Meeting Compendium of Papers

Subject/Index Terms

• TRT Terms: Design standards; Geometric design; Highway design; Highway factors in crashes; Highway safety; Roundabouts
• Geographic Terms: Italy
• Subject Areas: Design; Highways; Safety and Human Factors; I20: Design and Planning of Transport Infrastructure; I82: Accidents and Transport Infrastructure;

Filing Info

• Accession Number: 01477060
• Record Type: Publication
• Report/Paper Numbers: 13-2129
• Files: TRIS, TRB, ATRI
• Created Date: Mar 28 2013 4:46PM