EVALUATION OF FREEWAY NOISE BARRIERS

OF THE VARIOUS NOISE CONTROL METHODS, THE CONSTRUCTION OF FREEWAY NOISE BARRIERS IS OFTEN THE ONLY NOISE PROTECTIVE MEASURE THAT CAN BE DIRECTLY IMPLEMENTED ALONG EXISTING FREEWAYS BY A TRANSPORTATION DEPARTMENT. THIS PAPER DESCRIBES FIVE DIFFERENT NOISE BARRIERS, INCLUDING THEIR MATERIALS, TYPE OF SUPPORT, AND COSTS, CONSTRUCTED IN METROPOLITAN TORONTO AND PROVIDES DATA ON THEIR EFFECTIVENESS. THE RESULTS INDICATED THAT BARRIERS 10 TO 12 FT HIGH, LOCATED MIDWAY BETWEEN THE HOUSES AND THE PAVEMENT OR AT THE HIGHWAY SHOULDER, 60 TO 140 FT FROM THE NEAREST HOUSES, PROVIDED ONLY A 2- TO 6-DBA REDUCTION AT THE FIRST ROW OF HOUSES, 4 FT ABOVE GROUND. IMMEDIATELY BEHIND THE BARRIERS, WHERE THE REDUCTIONS ARE OF LITTLE REAL BENEFIT, REDUCTIONS OF 8 TO 14 DBA WERE ACHIEVED. IN ADDITION TO THE OVERALL FIT, REDUCTIONS OF 8 TO 14 DBA WERE ACHIEVED. IN ADDITION TO THE OVERALL DECREASE OF SOUND LEVELS, THE SOUND LEVEL FLUCTUATION, DEFINED AS THE STANDARD DEVIATION OF THE RECORDED SIGNAL, WAS DECREASED AT THE FIRST ROW OF HOUSES BY 0.4 TO 1.0 DBA. MEASURED SOUND LEVELS AND MEASURED REDUCTIONS DUE TO THE BARRIERS WERE COMPARED WITH CALCULATED SOUND LEVELS. IN GENERAL, CALCULATED REDUCTIONS DUE TO A BARRIER WERE OVERESTIMATED RATHER THAN UNDERESTIMATED. A VARIETY OF OTHER RESULTS AND CONCULSIONS RELATED TO THE INFLUENCE OF BARRIER HEIGHT, THE VERTICAL DISTRIBUTION OF SOUND LEVELS, AND THE EFFECTS OF CUT AND FILL SECTIONS WERE QUANTIFIED AND ARE DESCRIBED.

• Record URL:
  http://onlinepubs.trb.org/Onlinepubs/hrr/1973/448/448-006.pdf
• Availability:
  • Find a library where document is available. Order URL: http://worldcat.org/isbn/0309021790
• Supplemental Notes:
  • Publication of this paper sponsored by Task Force on Highways and the Environment. 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:
  • Harmelink, M D
  • Hajek, J J
• Conference:
  • 52nd Annual Meeting of the Highway Research Board
  • Location: Washington District of Columbia, United States
  • Date: 1973-1-22 to 1973-1-26
• Publication Date: 1973

Media Info

• Media Type: Digital/other
• Features: Figures; References; Tables;
• Pagination: pp 46-59
• Monograph Title: Noise abatement and control
• Serial:
  • Highway Research Record
  • Issue Number: 448
  • Publisher: Highway Research Board

Subject/Index Terms

• TRT Terms: Costs; Economic efficiency; Freeways; Height; Noise barriers; Sound level
• Uncontrolled Terms: Efficiency
• Subject Areas: Design; Economics; Finance; Highways;

Filing Info

• Accession Number: 00203846
• Record Type: Publication
• ISBN: 0309021790
• Files: TRIS, TRB
• Created Date: Jan 11 1974 12:00AM