Traffic Performance of Short-Distanced Traffic Lights with Probabilistic Spillback

Queues at controlled intersections play an important role in the performance of urban networks, as they are a main determinant of the delay experienced by the drivers. These queues have upper bounds, which, once exceeded, cause extra delays also to other links and other traffic streams. Often this effect is neglected in practice, or it is calculated as a deterministic phenomenon. In this paper the authors describe queue length probabilities at each moment in time for closely-spaced pre-timed traffic lights, using renewal theory. Special attention is given to the influence of the upstream signal settings on the downstream arrival pattern, and to the effects of downstream queues to the upstream signal, which can be blocked temporarily due to an excess of the available buffer space. Based on this model, a case study is used to illustrate the performance of uncoordinated signals. We show that if two signals are not well coordinated and if insufficient green is assigned to the downstream direction spillback will be likely to occur, causing extra delay in the system even when the signal is under saturated.

• Corporate Authors:

  Transportation Research Board

  500 Fifth Street, NW
  Washington, DC  United States  20001
• Authors:
  • Viti, Francesco
  • Tampere, Chris M J
  • Frederix, Rodric
• Conference:
  • Transportation Research Board 88th Annual Meeting
  • Location: Washington DC, United States
  • Date: 2009-1-11 to 2009-1-15
• Date: 2009

Language

• English

Media Info

• Media Type: DVD
• Features: Figures; References;
• Pagination: 18p
• Monograph Title: TRB 88th Annual Meeting Compendium of Papers DVD

Subject/Index Terms

• TRT Terms: Operations; Traffic delays; Traffic flow; Traffic oversaturation; Traffic queuing; Traffic signal control systems; Traffic signal timing; Urban highways
• Uncontrolled Terms: Downstream traffic; Spillback effects (Traffic); Upstream traffic
• Subject Areas: Highways; Operations and Traffic Management; I73: Traffic Control;

Filing Info

• Accession Number: 01126656
• Record Type: Publication
• Report/Paper Numbers: 09-2856
• Files: TRIS, TRB
• Created Date: Apr 17 2009 9:56AM