Evaluating the effects of prohibiting left turns and the resulting U-turn movement : summary report.

Details

• Creators:
  Chowdhury, Mashrur A. ; Derov, Nichole ; Tan, Paulin
• Corporate Creators:
  University of Dayton. Department of Civil and Environmental Engineering and Engineering Mechanics
• Corporate Contributors:
  Ohio. Dept. of Transportation
• Subject/TRT Terms:
  • Left turns
  • U turns
  • Traffic flow
  • Interchanges
  • Traffic safety
  • Traffic flow
  • Traffic safety
  • Roads--Interchanges and intersections--Safety measures
• Publication/ Report Number:
  FHWA/OH-2003/001
• Resource Type:
  Tech Report
• Geographical Coverage:
  Ohio
• Edition:
  Summary report.
• Corporate Publisher:
  University of Dayton. Dept. of Civil and Environmental Engineering and Engineering Mechanics
• Abstract:
  The objective of this research was to evaluate the operational and safety effects of restricting direct left turns from a driveway and providing alternatives to accommodate the left turn deterred traffic. This study was conducted in three phases: survey of state agencies, operational analysis, and safety assessment. Very little operational difference was found between no restrictions on direct left turns versus the restrictions with the U-turn alternative movements from site to site. While changes in the traffic volumes on the mainline had an impact in specific instances, no definite trends were apparent. As a result of all findings in this study, it is proposed that alternatives must be evaluated on a site-by-site basis. This study also found the jughandle design to be a superior alternative for accommodating left-turn deterred traffic for multi-lane divided and undivided sites compared to mid-block or intersection U-turns. The safety assessment revealed that a right turn followed by a U-turn movement is safer than the direct left turn.
• Format:
  PDF
• Funding:
  150037
• Download URL:
  https://rosap.ntl.bts.gov/view/dot/17545/dot_17545_DS1.pdf
• File Type:
  [PDF - 51.29 KB]
• Collection(s):
  US Transportation Collection
• Main Document Checksum:
  urn:sha256:7ef4b587798feec792dbf64703b78f4d70e283633541000215dd68aec7824178