VEHICLE SPRAY PATTERN STUDY

SPRAY PATTERNS FROM PASSING VEHICLES WERE INVESTIGATED TO DETERMINE THE OPTIMUM LATERAL AND VERTICAL PLACEMENT OF MILE POST MARKERS FOR AN INTERSTATE-TYPE HIGHWAY WITH WIDE, PAVED SHOULDERS. QUANTITATIVE DATA ARE PRESENTED FROM HIGHWAY TEST INSTALLATIONS OVER AN 18-MONTH STUDY PERIOD. DAYTIME BRIGHT- NESS RETENTION WAS VERY HIGH, AND NO VEHICLE SPRAY PATTERN OR ACCUMULATION RATE WAS OBTAINABLE FROM THESE DATA. PHOTOGRAPHS SHOW THE CHANGE IN APPEARANCE OF THE SIGNS AFTER THE 18-MONTH TEST PERIOD, BUT DO NOT GIVE A TRUE COMPARISON OF THE RELATIVE BRIGHTNESS OF THE SIGNS. NIGHTTIME BRIGHT- NESS READINGS OF REFLEX REFLECTION PROVED TO BE THE MOST EFFECTIVE INSTRUMENTATION IN DETERMINING THE VEHICLE SPRAY PATTERN. FROM ISO-BRIGHTNESS CURVES SHOWING BANDS OF EQUAL NIGHTTIME BRIGHTNESS RETENTION, THE OPTIMUM SIGN PLACEMENT WAS 14 FT OUT AND 6 FT ABOVE THE EDGE OF THE PAVEMENT. PLACING SIGNS AT THIS LOCATION WOULD HAVE RESULTED IN A NIGHTTIME BRIGHTNESS RETENTION OF OVER 50 PERCENT FOR ALL THE TEST SIGNS IN THIS STUDY.

Media Info

  • Media Type: Print
  • Features: Figures; References;
  • Pagination: pp 38-52
  • Monograph Title: Night visibility
  • Serial:

Subject/Index Terms

Filing Info

  • Accession Number: 00219872
  • Record Type: Publication
  • Report/Paper Numbers: HS-000 708
  • Files: TRIS, TRB
  • Created Date: Sep 5 1994 12:00AM