HEADWAY GROUPINGS

TIME HEADWAYS OF TRAFFIC WERE STUDIED TO IMPROVE THE UNDERSTANDING OF TRAFFIC BEHAVIOR. THE RELATIONSHIP BETWEEN THE OVERALL HEADWAY DISTRIBUTION AND THE VARYING LEVELS OF TRAFFIC OPERATIONS, FROM FREE FLOW TO CONGESTION, WERE INVESTIGATED SEPARATELY FOR PLATOON VEHICLES AND NON-PLATOON VEHICLES WHICH WERE KNOWN AS GROUP VEHICLES. KNOWLEDGE OF THE BEHAVIOR OF THE COMPONENT PARTS OF A TRAFFIC STREAM MAY BE VALUABLE IN THE DESIGN OF FREEWAY TRAFFIC CONTROL SCHEMES AND SIMULATION MODELS. PLATOON DEFINITIONS OF 2.0 OR 2.5 SEC APPEARED TO BE THE BEST CHOICES WITH A STUDY INTERVAL OF 0.5 SEC. PLATOON HEADWAYS WERE INDEPENDENT OF BOTH THE NUMERICAL SIZE OF THE PLATOON IN WHICH THEY OCCUR AND THEIR RELATIVE POSITION WITHIN THAT PLATOON. THE CHARACTERISTIC VOLUME, WHICH IS DERIVED FROM TIME MEAN HEADWAY OF PLATOONS, ENABLES COMPARISON OF GEOMETRIC DESIGN, LOCATION, LANE POSITION AND POSSIBLY VARIOUS DRIVER GROUPS. THE INDEPENDENCE OF PLATOONS AND GROUPS INFERS THAT PRIOR KNOWLEDGE OF A PRECEDING PLATOON OR GROUP DOES NOT EFFECTIVELY AID IN THE PREDICTION OF THE CHARACTER OF A SUCCEEDING PLATOON OR GROUP. THIS RESULT IS SIGNIFICANT WHEN CONSIDERING ANY TYPE OF PREDICTIVE CONTROL SYSTEM.

• Record URL:
  http://onlinepubs.trb.org/Onlinepubs/hrr/1965/72/72-007.pdf
• Supplemental Notes:
  • Distribution, posting, or copying of this PDF is strictly prohibited without written permission of the Transportation Research Board of the National Academy of Sciences. Unless otherwise indicated, all materials in this PDF are copyrighted by the National Academy of Sciences. Copyright © National Academy of Sciences. All rights reserved
• Authors:
  • Athol, Patrick
• Publication Date: 1965

Language

• English

Media Info

• Media Type: Print
• Features: Appendices; Figures; Tables;
• Pagination: pp 137-155
• Monograph Title: Traffic flow characteristics 1963 and 1964
• Serial:
  • Highway Research Record
  • Issue Number: 72
  • Publisher: Highway Research Board

Subject/Index Terms

• TRT Terms: Alternatives analysis; Drivers; Evaluation; Freeway operations; Freeways; Geometric design; Headways; Location; Traffic congestion; Traffic control; Traffic flow; Traffic lanes; Traffic platooning; Traffic simulation; Traffic surveys; Traffic volume
• Uncontrolled Terms: Characteristics; Traffic studies
• Old TRIS Terms: Lanes
• Subject Areas: Highways; Operations and Traffic Management;

Filing Info

• Accession Number: 00226994
• Record Type: Publication
• Report/Paper Numbers: HS-006 579
• Files: TRIS, TRB
• Created Date: Aug 13 2004 6:55PM