ROAD SURFACE REFLECTANCE MEASUREMENTS IN ONTARIO

A photometer for measuring surface reflectance matrices of dry pavements was developed at the University of Toronto and has been used to measure the light reflectance properties of many pavements in Ontario. The laboratory measurements were carried out on 6-in. diameter samples, and statistical deviations were carefully studied to determine the feasibility of classifying the pavements in accordance with Committee International de l'Eclairage (CIE) and (more recent) Illumination Engineering Society (IES) practice and to establish a reliable sampling procedure. The measured pavement types were classified on the basis of their reflectance parameters (Q0, S1, S2) established as average values from reflectance matrices of at least three samples. These parameters were found to be dependent on aggregate polishing and stone brightness, and on accumulated traffic load. The influence on the light reflectance of the viewing angle a being different from the standard 1 degree was also studied, and it was found that all parameters tend to decrease with increasing angle a. The findings indicate that reflection properties can be measured with fair accuracy and confidence, but that significant fluctuations of the reflectance properties can occur on a given pavement. The IES or CIE proposal for four specularity classifications under dry conditions can be recommended; however, the brightness parameter, Q0, was found to be of greater significance in lighting than originally anticipated and more accurate values should be established as discussed in this paper.

• Record URL:
  http://onlinepubs.trb.org/Onlinepubs/trr/1984/996/996-006.pdf
• Summary URL:
  https://scholar.google.com/scholar_lookup?title=ROAD+SURFACE+REFLECTANCE+MEASUREMENTS+IN+ONTARIO&author=W.+Jung&author=A.+Kazakov&author=A.+Titishov&publication_year=1984
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• 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. Publication of this paper sponsored by Committee on Visibility.
• Corporate Authors:

  Transportation Research Board

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• Authors:
  • Jung, W
  • Kazakov, A
  • Titishov, A I
• Publication Date: 1984

Media Info

• Media Type: Print
• Features: Figures; Photos; References; Tables;
• Pagination: pp 24-37
• Monograph Title: MOTORIST INFORMATION NEEDS AND VISIBILITY FACTORS
• Serial:
  • Transportation Research Record
  • Issue Number: 996
  • Publisher: Transportation Research Board
  • ISSN: 0361-1981

Subject/Index Terms

• TRT Terms: Accuracy; Brightness; Measuring instruments; Photometers; Reflectivity; Sampling; Surface course (Pavements)
• Uncontrolled Terms: Reflectance
• Geographic Terms: Ontario (Province)
• Subject Areas: Highways; Operations and Traffic Management; Safety and Human Factors; I73: Traffic Control;

Filing Info

• Accession Number: 00450256
• Record Type: Publication
• ISBN: 0309038057
• Report/Paper Numbers: HS-038 911
• Files: HSL, TRIS, TRB
• Created Date: Nov 30 1985 12:00AM