A STUDY OF MERGING AT URBAN GRADE-SEPARATED INTERCHANGES

During the summer of 1973, a total of 22 time-lapse films were made of merging at 12 urban sites in England. The main roads were motorways or high capacity dual-carriageways joined by slip roads at grade-separated interchanges. The sites covered a range of lanes, acceleration lanes, merge angles, gradients etc., together with a range of main road and slip road flows. The data extracted from the films were coded on to punched cards for computer analysis, the output of which was used in an attempt to model upstream nearside lane flow and merge capacity. The paper gives a brief description of the sites and some critical comment on the survey method, and its manpower requirements are given. An equation, which gave a satisfactory correlation, for the nearside lane flow in terms of traffic flow and certain geometric parameters is offered. Good correlation was not obtained in any of the attempts to model merge capacity, but some suggestions are made for the guidance of designers. /Author/TRRL/

Language

  • English

Media Info

  • Features: Photos; References; Tables;
  • Pagination: p. 1-8
  • Serial:
    • Volume: 8
    • Issue Number: 1

Subject/Index Terms

Filing Info

  • Accession Number: 00164162
  • Record Type: Publication
  • Source Agency: Transport and Road Research Laboratory (TRRL)
  • Files: ITRD, TRIS, ATRI
  • Created Date: Jun 28 1978 12:00AM