DERIVATION AND APPLICATION OF CONGESTION THRESHOLDS IN THE ESTIMATION OF MOTORWAY LINK 'CAPACITY'

This paper reviews the methodology used to calculate Congestion Reference Flows (CRF) to demonstrate the sensitivity of maximum link flow thresholds to the constituent formula parameters. It uses illustrative data from a dual 3-lane commuter motorway and a dual 3- lane strategic inter-urban motorway in the in the UK to demonstrate the responsiveness of flow thresholds to the percentage of HGVs and PSVs, peak to daily ratios and tidality. Having established CRF thresholds for both motorways, these are then used to determine the years in which these thresholsds are exceeded. The paper concludes by identifying the limitations of the current method for estimating motorway reference flows. Recommendations are made for refining the formula. For the covering abstract see IRRD 869153.

• Availability:
  • Find a library where document is available. Order URL: http://worldcat.org/isbn/0860502724
• Corporate Authors:

  PTRC Education and Research Services Limited

  Glenthorne House, Hammersmith Grove
  London W6OL9,   England 
• Authors:
  • Tucker, B
  • FICKLING, R
• Conference:
  • HIGHWAYS. PROCEEDINGS OF SEMINAR K HELD AT THE PTRC EUROPEAN TRANSPORT FORUM, UNIVERSITY OF WARWICK, ENGLAND, SEPTEMBER 12-16, 1994. VOLUME P382
• Publication Date: 1994-9

Language

• English

Media Info

• Features: References;
• Pagination: p. 145-59

Subject/Index Terms

• TRT Terms: Buses; Calculation; Conferences; Freeways; Mathematical models; Peak periods; Traffic congestion; Traffic flow; Trucks; Ultimate load design
• ITRD Terms: 1272: Bus; 6464: Calculation; 8525: Conference; 632: Congestion (traffic); 6452: Limit; 1236: Lorry; 6473: Mathematical model; 2752: Motorway; 612: Peak hour; 671: Traffic flow
• Subject Areas: Data and Information Technology; Design; Motor Carriers; Operations and Traffic Management; Public Transportation;

Filing Info

• Accession Number: 00681014
• Record Type: Publication
• Source Agency: Transport Research Laboratory
• ISBN: 0-86050-272-4
• Files: ITRD
• Created Date: Jul 20 1995 12:00AM