A REVIEW OF ROAD DESIGN IN RELATION TO ROAD SAFETY
The study is related to the proposition that the design of the roadway affects the accident rate in so far as it directly affects the way in which vehicles move along it. A further proposition is that road design plays an important part in the amelioration of accidents. This study is a review and inventory of literature and does not constitute a research or policy statement on the subject. Much of the literature is in the form of design reports of specific research topics which indicate the best methods for constructing certain features, but which do not necessarily analyze accident figures. Road design must minimize points of conflict between vehicles; thus intersections, median openings and gutter crossings should be kept to a minimum consistent with other aspects of service. The road should be designed with a uniform standard of facility, not widening lanes over 11 feet. Increased shoulder width will decrease accidents provided shoulders are restricted to emergency use. Skidding accidents are low if a high co-efficient of friction of the pavement surface is maintenaned. Reconstruction should ease curves, widen bridges and increase sight distance. Major traffic streams on main roads reduce accidents, as do T-intersections, separate median lanes for right turns, curve delineation and four-lane divided highways with full access control. At interchanges diamond ramps are safer than cloverleaf ramps and acceleration and deceleration lanes should be at least 800 feet long. Traversible medians should be at least 30 feet wide and an obstacle free area 30 feet from the pavement edge of high speed roads should be provided. Breakaway light and sign supports are recommended as are crash barriers. Research items should be directed toward an improved method of ranking road safety improvement projects for Australia.
Department of Transport, AustraliaP.O. Box 367
Canberra, A.C.T., Australia
- Publication Date: 1973-6
- Features: References; Tables;
- Pagination: 135 p.
- TRT Terms: Breakaway supports; Crash rates; Curves (Geometry); Diamond interchanges; Highway design; Highway safety; Median lanes; Pavements; Reviews; Surface course (Pavements); T intersections; Texture
- Subject Areas: Design; Highways; Pavements; Safety and Human Factors;
- Accession Number: 00098452
- Record Type: Publication
- Source Agency: National Safety Council Safety Research Info Serv
- Report/Paper Numbers: NR/11
- Files: TRIS
- Created Date: Oct 18 1975 12:00AM