ACCIDENTS AT 4-ARM ROUNDABOUTS

This is a digest of a report (LR 1120) which gives the findings of a study of personal injury accidents occurring during the years 1974-1979 at a sample of 84 four-arm traffic circles on main roads in the United Kingdom. The study produced accident tabulations which give insights into the main accident problems at roundabouts and derived relationships between accident frequencies, traffic flow and geometry which could be used in design and appraisal. The traffic circles studied included "small" traffic circles and those of conventional design. The tabulations presented show accident frequencies, severities, and accident rates by traffic circle type. The results of analyses of accidents by traffic circle type, the disaggregation of accidents by type of road user, analysis of the temporal distribution of accidents, analysis using linear modelling methodology, and regression analyses are described. The question of errors in prediction is discussed and suggestions are made for updating the model predictions over time.

• Corporate Authors:

  Transport and Road Research Laboratory (TRRL)

  Wokingham, Berkshire  United Kingdom 
• Authors:
  • MAYCOCK, G
  • HALL, R D
• Publication Date: 1984

Media Info

• Features: Tables;
• Pagination: 2 p.

Subject/Index Terms

• TRT Terms: Analysis; Crash rates; Crash severity; Data tables; Errors; Forecasting; Geometric design; Injuries; Mathematical models; Regression analysis; Research; Traffic circles; Traffic crashes; Traffic flow; Travelers
• Uncontrolled Terms: Models
• Old TRIS Terms: Linear method
• Subject Areas: Data and Information Technology; Highways; Research; Safety and Human Factors; Society;

Filing Info

• Accession Number: 00399272
• Record Type: Publication
• Source Agency: National Highway Traffic Safety Administration
• Report/Paper Numbers: Digest LR 1120, HS-038 313
• Files: HSL, TRIS, ATRI, USDOT
• Created Date: Sep 30 1985 12:00AM