FACTORS AFFECTING TRAFFIC OPERATIONS ON SEVEN-LANE CROSS SECTIONS. FINAL REPORT

Previous research has documented the operational and safety benefits of installing a two-way left-turn lane (TWLTL) on two-lane and four-lane arterials. Unfortunately, very little research has been performed to quantify the effects of seven-lane cross sections on traffic operations and safety. The goal of this research was to provide information on the factors that affect traffic operations on seven-lane cross sections in urban and suburban areas. Field studies were conducted to evaluate the effects of these factors. Acceleration noise, a measure of the relative smoothness of a trip, was used to assess the impacts of these factors on operations. Acceleration noise was collected in each lane in both directions during four periods (A.M. Peak, Off-peak, Noon, and P.M. Peak) at nine sites throughout Texas with different roadway and roadside development characteristics. From the studies, it was found that the quality of flow on seven-lane cross sections is impacted by such roadway and roadside development factors as the density of the driveways located on each side of the roadway, the average daily traffic carried by a roadway, and the average number of unsignalized intersection approaches along each side of the roadway. Generally, as the density of driveways and the amount of traffic carried on a roadway increase, the ability of the driver to maintain a trip with few changes in speed decreases. Therefore, designers should carefully consider not just the overall type of development and traffic demands on a roadway, but also the specific type of roadway and roadside development characteristics on each side of the roadway when considering implementing seven-lane cross sections in urban and suburban arterials.

• Supplemental Notes:
  • Research study title: The Use of Continuous Two-Way Left-Turn Lanes on High-Speed Rural and Suburban Highways.
• Corporate Authors:

  Texas Transportation Institute

  Texas A&M University System, 1600 E Lamar Boulevard
  Arlington, TX  United States  76011

  Texas Department of Transportation

  Research and Technology Transfer Office, P.O. Box 5051
  Austin, TX  United States  78763-5051

  Federal Highway Administration

  1200 New Jersey Avenue, SE
  Washington, DC  United States  20590
• Authors:
  • Balke, K N
  • Fitzpatrick, K
  • Lienau, T
• Publication Date: 1993-11

Language

• English

Media Info

• Features: Appendices; Figures; References; Tables;
• Pagination: 86 p.

Subject/Index Terms

• TRT Terms: Average daily traffic; Driveways; Field studies; Highway operations; Noise sources; Suburbs; Traffic; Traffic noise; Two way left turn lanes; Unsignalized intersections; Urban areas
• Old TRIS Terms: Acceleration noise; Seven lane cross sections; Two way left turn
• Subject Areas: Highways; Operations and Traffic Management; I73: Traffic Control;

Filing Info

• Accession Number: 00662783
• Record Type: Publication
• Report/Paper Numbers: FHWA/TX-94/1293-2F, Res Rept 1293-2F, TTI: 0-1293
• Contract Numbers: Study 0-1293
• Files: TRIS, USDOT, STATEDOT
• Created Date: Jul 5 1994 12:00AM