Roadway Median Treatments – Phase 1 and Phase 2

This research project examined relationships among crash rates, cross section design elements, and other operational attributes of multilane urban and suburban roadways in Arkansas. Crash rates for four cross section categories (roadways with no median, roadways with occasional left-turn lanes, roadways with continuous two-way left turn-lanes, and roadways with raised or depressed medians) were compared. Freeways were not considered. Crash histories were examined for cross section types, speed limits, volumes, widths of through lanes, presence of curb or shoulder, outer shoulder widths, median widths, and the densities of various types of access. Some variables were correlated, and it was suspected that such correlations can skew crash prediction models. Generally, the raised or depressed median group had slightly lower crash rates. The findings can help planners and designers when selecting the median type and cross section design for multilane roadways in rural areas that face future urban development, and in urban areas.

• Record URL:
  https://ardot.gov/System_Info_and_Research/research/Library/MBTC/MBTC2055_(Phase_I)_and_MBTC2067_(Phase_II).PDF
• 
• Record URL:
  https://rosap.ntl.bts.gov/view/dot/17601
• Supplemental Notes:
  • This research was sponsored by the U.S. Department of Transportation, University Transportation Centers Program.
• Corporate Authors:

  Mack-Blackwell Transportation Center

  University of Arkansas, 4190 Bell Engineering Center
  Fayetteville, AR  United States  72701

  Research and Innovative Technology Administration

  1200 New Jersey Avenue, SE
  Washington, DC  United States  20590
• Authors:
  • Gattis, J L
  • Duncan, L K
  • Tooley, M S
  • Brewer, A S
  • Le, M Q
  • Muthu, P
• Publication Date: 2010-2

Language

• English

Media Info

• Media Type: Web
• Edition: Final Report
• Features: Figures; Photos; References; Tables;
• Pagination: 82p

Subject/Index Terms

• TRT Terms: Crash rates; Highway design; Medians; Multilane highways; Speed limits; Traffic volume
• Uncontrolled Terms: Depressed medians; Lane width; Median treatments; Median width; Raised medians
• Geographic Terms: Arkansas
• Subject Areas: Design; Highways; Safety and Human Factors; I20: Design and Planning of Transport Infrastructure; I80: Accident Studies;

Filing Info

• Accession Number: 01153253
• Record Type: Publication
• Report/Paper Numbers: MBTC DOT 2055, MBTC DOT 2067
• Files: UTC, NTL, TRIS, USDOT
• Created Date: Mar 26 2010 7:59AM