LIMITED PRIORITY MERGE AT UNSIGNALIZED INTERSECTIONS

The development of a new gap acceptance model based on limited priority for the major-stream is discussed. Field observations were done to identify the merging mechanism taking place at unsignalized intersections under congested conditions. A limited priority system is proposed based on the assumption that the major-stream vehicles could be slightly delayed to accommodate the minor-stream vehicles. Equations for capacity in the limited priority system were presented assuming that the major-stream vehicles have a bunched exponential headway distribution and the minor-stream drivers are both consistent and homogenous. The gap acceptance model based on the limited priority was then applied to the performance of roundabouts. It was found that the limited priority merge can have a significant effect on the entry capacity at two-lane roundabouts. The relationship between the entry capacity and the circulating stream flow at two-lane roudabouts was very close to the straight-line relationship that has been found in the U.K. using an empirical method.

• Corporate Authors:

  Transportation Research Board

  500 Fifth Street, NW
  Washington, DC  United States  20001

  Federal Highway Administration

  1200 New Jersey Avenue, SE
  Washington, DC  United States  20590

  National Institute for Advanced Transportation Technology

  University of Idaho, Moscow
  115 Engineering Physics Building
  Moscow, ID  United States  83844-0901

  TransNow, Transportation Northwest

  University of Washington, Department of Civil Engineering
  129 More Hall, Box 352700
  Seattle, WA  United States  98195-2700
• Authors:
  • Troutbeck, T
  • Kako, S
• Conference:
  • Third International Symposium on Intersections Without Traffic Signals
  • Location: Portland, Oregon
  • Date: 1997-7-21 to 1997-7-23
• Publication Date: 1997-7

Language

• English

Media Info

• Features: Figures; References; Tables;
• Pagination: p. 294-302

Subject/Index Terms

• TRT Terms: Approach lanes; Bus priority; Gap acceptance; Headways; Highway capacity; Intersections; Merging traffic; Traffic delays; Traffic signal preemption; Unsignalized intersections
• Uncontrolled Terms: Intersection capacity
• Old TRIS Terms: Intersection approach
• Subject Areas: Highways; Operations and Traffic Management; Public Transportation; I73: Traffic Control;

Filing Info

• Accession Number: 00742529
• Record Type: Publication
• Files: TRIS, TRB, USDOT
• Created Date: Nov 8 1997 12:00AM