A queue-theoretical mode for describing motorway traffic flow is presented, in which the average driver's freedom of movement under given external conditions is quantified in a Markov Process (on the basis of a description of the action pattern of the individual drivers), and which uses the measurable variables of "state probabilities" and "transition intensities." The existence of correlation between these new variables and the conventional road traffic parameters, i.e. traffic volume and speed, has created the possibility for a quantitative assessment of factors which affect traffic flow. Fundamently, the road traffic model represents a method of interpreting the results of observations. A traffic engineering application of the model is described in which an attempt is made to show how traffic flow is affected by changes in traffic volume. The model can also be used in an analysis of the behavior of drivers on roads across bridges with a view to a formulation of capacity service level data. The model could be used in the evaluation of the effect of heavy vehicles on the traffic flow. The use of the road traffic model in the assessment of aspects of road geometry can be extended to comparison of the day and night time traffic flow as well as for the evaluation of the effect of road lighting on traffic flow. Applications of the model to determine details of cross-sections, curves in vertical & horizontal alignments etc. are also considered.

  • Corporate Authors:

    Ministry of Public Works, Denmark

    Road Department
    Copenhagen,   Denmark 
  • Authors:
    • Rorbech, J
  • Publication Date: 1974


  • English

Media Info

  • Features: Appendices; Figures; Photos; References; Tables;
  • Pagination: 241 p.

Subject/Index Terms

Filing Info

  • Accession Number: 00081622
  • Record Type: Publication
  • Source Agency: Transport and Road Research Laboratory (TRRL)
  • Report/Paper Numbers: Thesis
  • Files: ITRD, TRIS
  • Created Date: Apr 8 1975 12:00AM