Various highway noise shielding techniques (noise barriers, intervening houses and cut and fill sections) are evaluated and the results of field sound measurements are compared with results calculated by the BBN noise estimation method. Five different noise barrier types constructed in Metropolitan Toronto are described in terms of location, dimensions, materials, appearance, type of support and costs. The noise barriers, 10 to 12 feet high and located either midway between the houses and the pavement or at the highway shoulder, 60 to 140 feet from the nearest houses, provided only 2 to 6 dBA reduction at the first row of houses, 4 feet above ground. Immediately behind the barriers, where the reductions are of little real benefit, reductions of 8 to 14 dBA were achieved. Comparison of measured and calculated sound level reductions due to barriers indicates that the calculated reductions are overestimated rather than underestimated. Limited validation studies of the BBN noise estimation method show a need for further research particularly the areas of the vertical distribution of sound levels and attenuation of freeway noise with distance. The influence of materials and height of barriers were also examined. The results and conclusions of these studies are presented. Due to the relative barrier ineffectiveness, greater attention and emphasis should be given to other noise control measures such as housing modifications, land use control and control of vehicular noise emissions at the source. These are briefly described at the end of the report.

  • Corporate Authors:

    Ministry of Transportation and Communications, Canada

    Systems Research Branch
    Downsview, ONo,   Canada 
  • Authors:
    • Harmelink, M D
    • Hajek, J J
  • Publication Date: 1972-9

Media Info

  • Features: Figures; References; Tables;
  • Pagination: 38 p.

Subject/Index Terms

Filing Info

  • Accession Number: 00261236
  • Record Type: Publication
  • Report/Paper Numbers: MTC Rpt No. RR 180
  • Files: TRIS
  • Created Date: Oct 22 1974 12:00AM