DRIVER RESPONSE TO AN ICY BRIDGE WARNING SIGN

A FIELD EVALUATION WAS MADE OF DRIVER RESPONSE TO A WARNING SIGN WHICH READ "ICY BRIDGE AHEAD". WHEN NOT IN USE, THE SIGN WAS ROTATED OUT OF THE DRIVERS' LINE OF SIGHT. WHEN ACTIVATED, AN AMBER FLASHING LIGHT WAS MOUNTED ATOP THE SIGN AND ANOTHER ON THE UPSTREAM GUARDRAIL AT THE BRIDGE TO INCREASE VISIBILITY OF THE WARNING SYSTEM. THE TYPES OF DATA COLLECTED INCLUDE SPEED MEASUREMENTS, TRAFFIC DISTRIBUTION TO LANE, COUNTS OF LANE CHANGES, BRAKE LIGHT OCCURRENCES AND DRIVER INTERVIEWS. COMPARATIVE MEASUREMENTS WERE MADE WITH AND WITHOUT THE SIGNS. THE STUDY SITE AND WARNING SYSTEM ARE DESCRIBED IN DETAIL. THE KEY TRAFFIC CHARACTERISTIC WAS CHOSEN TO BE THE SPEEDS OF "ISOLATED" VEHICLES. DATA OF FLOW RATES AND DISTRIBUTION TO LANE, CHANGE FREQUENCY, AND BRAKE LIGHT ACTIVITY WERE ALSO RECORDED. DATA TECHNIQUES ARE OUTLINED. THE ANALYSIS OF SPEEDS WHICH CONSISTED OF THREE STEPS IS DESCRIBED. A PLAN VIEW OF THE SITE IS PRESENTED, AS ARE ALSO GRAPHS ILLUSTRATING SPEED DATA. IT IS CONCLUDED THAT THE MOST DECISIVE RESULT OF THE STUDY IS A SPEED REDUCTION EFFECTED BY THE SIGN. SEVERAL SUBJECTIVE CONCLUSIONS WHICH MERIT FURTHER EXPERIMENTAL STUDY ARE LISTED.

• Authors:
  • Kobett, D R
  • Glauz, W D
  • Balmer, G G
• Publication Date: 1972-7

Media Info

• Features: Figures; Photos; References; Tables;
• Pagination: p. 18-23
• Serial:
  • Traffic Engineering, Inst Traffic Engr
  • Volume: 42
  • Issue Number: 10

Subject/Index Terms

• TRT Terms: Alternatives analysis; Bridges; Data collection; Drivers; Ice; Reaction time; Studies; Traffic flow; Traffic signs; Traffic speed; Travel patterns; Warning signs
• Uncontrolled Terms: Comparative analysis; Driver reaction; Traffic patterns
• Old TRIS Terms: Flashing sign; Speed studies
• Subject Areas: Bridges and other structures; Highways; Operations and Traffic Management;

Filing Info

• Accession Number: 00226423
• Record Type: Publication
• Files: TRIS
• Created Date: Jan 11 1974 12:00AM