ESTIMATION OF TRAFFIC QUEUES AND DELAYS AT ROUNDABOUT ENTRIES

Queue lengths and delays at entry points are the important indices for measuring the performance of roundabouts. The object of this study is to find out suitable methods for estimating these indices. Several formulae for estimating average queue length and delay at roundabout entries have been developed. The well-known formulae are those developed by Kimber and Hollis. Field observations on queue lengths and delays at roudabout entries indicate Kimber's formulae provide reasonable predictions for under-saturated traffic conditions. New formulae, based on Kimber's formulae, are derived by introducing two new parameters, one for adjusting the deterministic equation and the other for increasing the approaching speed. The parameters used in this new formulae are determined on the basis of the average simulation data for oversaturated conditions. A computer program was developed to apply the research results in practice.

• 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:
  • Tan, J
• 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. 248-260

Subject/Index Terms

• TRT Terms: Approach lanes; Intersections; Queuing theory; Roundabouts; Schedules; Traffic characteristics; Traffic delays
• Uncontrolled Terms: Arrival time; Traffic conditions
• Old TRIS Terms: Intersection approach; Queueing models
• Subject Areas: Highways; Operations and Traffic Management; I73: Traffic Control;

Filing Info

• Accession Number: 00742514
• Record Type: Publication
• Files: TRIS, TRB, USDOT
• Created Date: Nov 5 1997 12:00AM