TRAFFIC CAPACITY

A SUMMARY IS PRESENTED OF A RESEARCH PROJECT TO DETERMINE CAPACITY OF TWO, THREE AND FOUR LANE ROADS. THE INFLUENCE OF THE PROPORTIONATE AMOUNT OF TRAFFIC IN ONE DIRECTION IS NOT MARKED ON 2-LANE ROADS UNTIL THE FRACTION INCREASES TO 80% OR MORE, WHEN A GREATER VOLUME OF TRAFFIC IS CARRIED WITHOUT CONGESTION. THE AVERAGE WORKING CAPACITY FOR 2-LANE ROADS IS APPROXIMATELY 95 PER 5-MINUTE INTERVAL OR 1000 PER HOUR. THREE-LANE ROADS APPEAR TO OPERATE TO SLIGHTLY BETTER ADVANTAGE WHEN 70% OF THE TRAFFIC IS IN ONE DIRECTION. THE AVERAGE WORKING CAPACITY IS APPROXIMATELY 180 PER FIVE-MINUTE INTERVAL OR 2000 PER HOUR. FOUR-LANE ROADS HAVE AN AVERAGE WORKING CAPACITY OF 290 VEHICLES PER 5-MINUTE INTERVAL. THE ADDITION OF ONE LANE TO A 2-LANE ROAD INCREASES ITS WORK 50% AND ITS CAPACITY 100%. ADDITION OF TWO LANES INCREASES THE WIDTH BY 100% AND THE CAPACITY BY 200%. HOWEVER, THIS STUDY RELATES TO TRAFFIC CAPACITY ONLY AND NO CONSIDERATION WAS GIVEN TO THE RELATIVE SAFETY OF THE VARIOUS LANE DESIGNS UNDER VARYING VOLUMES OF TRAFFIC.

  • Supplemental Notes:
    • Vol 11, Pt 1, PP 409-412, 2 FIG, 1 TAB
  • Authors:
    • Johnson, A N
  • Publication Date: 1932

Media Info

  • Monograph Title: Proceedings of the Eleventh Annual Meeting of the Highway Research Board Held at Washington, D.C. December 10-11, 1931. Part I: Reports of Research Committees and Papers
  • Serial:

Subject/Index Terms

Filing Info

  • Accession Number: 00227991
  • Record Type: Publication
  • Files: TRIS, TRB
  • Created Date: Jun 1 1971 12:00AM