Speed-flow Models for Freeways

The new Highway Capacity Manual (HCM) 2010 proposes in chapter 11 two-stage curves to represent the speed-flow diagram for non-congested flow on freeways where constant speeds are postulated over a rather wide range of volumes. This division of the traffic flow in two parts plus the congested conditions is a rather pragmatic approach. Further the three steps pretend three separate traffic flow regimes, which don’t exist. A continuous function, like it is used in the other guidelines, would replicate the traffic conditions comprehensibly and realistically. Therefore, a model based on simple queueing theory analogy is presented to represent the non-congested part of traffic flow. Moreover several models which represent each state of traffic flow by one function are discussed. These different approaches are compared to real world data from the United States and Germany. Based on this analysis a new single-stage model for the approximation of fundamental diagrams for freeways is recommended. The model can also be modified in order to represent the capacity drop effect

• Record URL:
  • http://ac.els-cdn.com/S1877042811009724/1-s2.0-S1877042811009724-main.pdf?_tid=aae82b8d128a3002fde392eeaa6f1b06&acdnat=1333993327_39f1925563ef66a2e2918f9f7f5329e7
• Availability:
  • Find a library where document is available. Order URL: http://worldcat.org/issn/18770428
• Supplemental Notes:
  • Abstract reprinted with permission from Elsevier.
• Authors:
  • Brilon, Werner
  • Lohoff, Jan
• Conference:
  • 6th International Symposium on Highway Capacity and Quality of Service
  • Location: Stockholm , Sweden
  • Date: 2011-6-28 to 2011-7-3
• Publication Date: 2011

Language

• English

Media Info

• Media Type: Digital/other
• Features: Figures; References; Tables;
• Pagination: pp 26-36
• Monograph Title: 6th International Symposium on Highway Capacity and Quality of Service
• Serial:
  • Procedia - Social and Behavioral Sciences
  • Volume: 16
  • Publisher: Elsevier
  • ISSN: 1877-0428
  • Serial URL: http://www.sciencedirect.com/science/journal/18770428/53
• Publication flags:

  Open Access (libre)

Subject/Index Terms

• TRT Terms: Flow by speed; Freeways; Highway capacity; Queuing theory; Traffic flow
• Geographic Terms: Germany; United States
• Subject Areas: Highways; Operations and Traffic Management; Planning and Forecasting; I71: Traffic Theory;

Filing Info

• Accession Number: 01367464
• Record Type: Publication
• Files: TRIS
• Created Date: Apr 10 2012 3:17PM