A COMPARISON OF THE SAFETY POTENTIAL OF THE RAISED VERSUS DEPRESSED MEDIAN DESIGN

This paper examines the safety benefits of the mound (raised) median design as compared to the swale (depressed) median design for Interstate highway medians having an 84-ft (25.60m) design width. The effects of each median design on the frequency and severity of median-involved single- vehicle accidents, on the path of the encroaching vehicle, and on the vehicle's tendency to overturn were studied. Approximately 130 miles (209 km) of 4-lane, divided highway with each median design were studied, and the accident experience from 1969 through 1971 was analyzed. The results indicated that the 84-ft median of either cross-sectional design provides a generally adequate recovery area for encroaching vehicles, although the swale median appears to provide more opportunity for encroaching vehicles to regain control and return to their roadway. The use of either cross-sectional design for medians of this width has no effect on the primary path of the vehicle, on the vehicle's tendency to overturn, or on the resulting severity of the accident when a median encroachment results in a reported accident.

Media Info

  • Media Type: Print
  • Features: Figures; References; Tables;
  • Pagination: pp 1-15
  • Monograph Title: Traffic operations
  • Serial:

Subject/Index Terms

Filing Info

  • Accession Number: 00083966
  • Record Type: Publication
  • ISBN: 0309023580
  • Files: TRIS, TRB
  • Created Date: Apr 8 1975 12:00AM