MEASUREMENT OF DRIVER REACTIONS TO TUNNEL CONDITIONS

ANALYSES BY THE PORT OF NEW YORK AUTHORITY STAFF INDICATED DIFFERENCES IN TRAFFIC FLOW BETWEEN DIFFERENT TUNNELS. AFTER DISCUSSION OF THESE AND BECAUSE OF PREVIOUS HEADWAY STUDIES BY THE SENIOR AUTHOR, IT WAS THOUGHT THAT DRIVER REACTIONS TO CONDITIONS OF TUNNEL TRAFFIC MIGHT BE BASIC TO DIFFERENCES IN TRAFFIC FLOW. ACCORDINGLY, EXPERIMENTS WERE DESIGNED TO SIMULATE THE CLOSE FOLLOWING OF HEAVY TRAFFIC DRIVING TO MEASURE EFFECTS ON DRIVER REACTIONS OF DIFFERENT COMBINATIONS OF CURVE, GRADE AND, IN TUNNELS, OF DIFFERENT CHARACTERISTICS IN THE PITTSBURGH AREA. ANALYSIS OF PHOTOGRAPHIC MEASUREMENTS SHOWED THAT INCREASES OF TIME- HEADWAY RESULTED FROM EXPERIMENTAL DECELERATIONS. VARIATIONS OF TIME-HEADWAYS AND DRIVER-LAGS WERE RELATED TO THESE DIFFERENT HIGHWAY CHARACTERISTICS THESE DATA ARE OF BOTH PRACTICAL AND THEORETICAL IMPORTANCE SINCE THEY ACCOUNT FOR MAJOR DIFFERENCES IN SELF-LIMITATION OF FLOW. THIS HAS BEEN NOTED PREVIOUSLY BUT NOT EXPLAINED. ON THE BASIS OF THESE MEASUREMENTS, PREDICTIONS OF EFFECTS IN NEW YORK TUNNELS WERE MADE. A SHORT EXPERIMENTAL SERIES WAS RUN IN WHICH EACH DRIVER DROVE IN EACH OF THREE TUNNELS. TIME-HEADWAY INCREASES RESULTING FROM A DECELERATION WOULD ACCOUNT FOR THE GENERAL ORDER OF MAXIMUM TRAFFIC FLOW RECORDED. MEASUREMENTS INDICATED THAT DOWNGRADE, RIGHT CURVE, LOWER ILLUMINATION, AND EVEN PSYCHOLOGICAL CONSTRICTION TENDED TO REDUCE FLOW. THE RESULTS FURNISH BASIC DATA FOR MATHEMATICAL STUDIES OF TRAFFIC FLOW WHICH RESULTS IN DIFFERENT TRAFFIC- VOLUME OR TRAFFIC-DENSITY RELATIONSHIPS IN DIFFERENT TRAFFIC SAMPLES. PRACTICAL IMPLICATIONS FOR INCREASING MAXIMUM FLOW WITH SAFETY ARE SUGGESTED. /AUTHOR/

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  • Supplemental Notes:
    • Vol 37, pp 345-357, 8 FIG, 5 TAB, 2 REF. 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:
    • Forbes, T W
    • Zagorski, H J
    • Holshouser, E L
    • Deterline, W A
  • Publication Date: 1958

Media Info

  • Media Type: Digital/other
  • Monograph Title: Proceedings of the Thirty-Seventh Annual Meeting of the Highway Research Board, Washington, D.C., January 6-10, 1958
  • Serial:

Subject/Index Terms

Filing Info

  • Accession Number: 00223533
  • Record Type: Publication
  • Files: TRIS, TRB
  • Created Date: Sep 27 1971 12:00AM