Sydney has a number of three lane tidal flow bridges on major arterial roads where they cross Sydney harbour and adjacent rivers. Until recently the tidal flow direction on these bridges was controlled manually using electrically operated signs and placement of "candy bars". This arrangement was only a compromise and still caused large delays on occasions when the tidal directions were not changed at the right time or when the demand in both directions exceeded the capacity of a single lane. The paper describes a traffic responsive automatic system using moveable median islands and electric signs controlled locally by a modified microprocessor traffic controller and strategically by the Sydney co-ordinated adaptive traffic system (SCATS). The traffic requirements and the control algorithms are discussed as well as the mechanical and electrical design of the system. The design considerations employed to ensure a system of high safety and reliability are covered. (Author/TRRL)

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  • Supplemental Notes:
    • This paper was presented during the 12th Australian Road Research Board Conference, Hobart, Tasmania, 27-31 August 1984.
  • Corporate Authors:


    Melbourne, Victoria  Australia 
  • Authors:
    • Longfoot, J E
  • Publication Date: 1984

Media Info

  • Features: Figures; References; Tables;
  • Pagination: p. 155-166
  • Serial:

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Filing Info

  • Accession Number: 00393469
  • Record Type: Publication
  • Source Agency: ARRB
  • Files: ITRD, TRIS, ATRI
  • Created Date: Jul 31 1985 12:00AM