Fundamental Diagram for Signalized Arterials: An Empirical Analysis Using High-Resolution Traffic Data

The fundamental diagram, as a foundation of traffic flow theory, macroscopically describes the relationship between traffic flow and density. Up to now, most research on the fundamental diagram has focused on uninterrupted traffic flow; however, the fundamental diagram for signalized arterial is still treated as a “myth.” This is partly due to the complexity of the interrupted nature of arterial traffic flow; and partly because of the lack of detailed arterial data. Utilizing the high resolution event-based signal data collected by the SMART-SIGNAL system (Systematic Monitoring of Arterial Road Traffic and Signals) developed at the University of Minnesota, this research first describes some unique features of the arterial fundamental diagram caused by signal operations. In particular, two capacities are shown with cycle-based flow-occupancy data. The authors explain the inner mechanism of such phenomena by developing a normalization procedure, which normalizes the arterial fundamental diagrams by green ratio vertically and by “deceleration-stop-acceleration” horizontally. It is found that the arterial fundamental diagrams can be converted to the similar fundamental diagrams from uninterrupted traffic flow by applying the normalization procedure. In addition, this research analyzes the impact of signal coordination.

• Corporate Authors:

  Transportation Research Board

  500 Fifth Street, NW
  Washington, DC  United States  20001
• Authors:
  • Liu, Henry X
  • Wu, Xinkai
  • Geroliminis, Nikolas
• Conference:
  • Symposium on the Fundamental Diagram: 75 Years (Greenshields 75 Symposium)
  • Location: Woods Hole Massachusetts, United States
  • Date: 2008-7-8 to 2008-7-10
• Publication Date: 2008

Language

• English

Media Info

• Media Type: CD-ROM
• Features: Figures; References;
• Pagination: 19p
• Monograph Title: Symposium on the Fundamental Diagram: 75 Years (Greenshields 75 Symposium), July 8-10, 2008, Woods Hole, MA. Preprints

Subject/Index Terms

• TRT Terms: Arterial highways; Macroscopic traffic flow; Traffic density; Traffic flow theory; Traffic signal control systems; Uninterrupted flow
• Uncontrolled Terms: Fundamental diagram
• Subject Areas: Highways; Operations and Traffic Management; I71: Traffic Theory;

Filing Info

• Accession Number: 01109356
• Record Type: Publication
• Files: TRIS, TRB
• Created Date: Aug 25 2008 8:11AM