Field measurements of noise were made near a railroad retarder system without barriers and with acoustical barriers of various configurations. The configurations tested included acoustically reflective and acoustically absorptive barriers with heights of 4 to 12 feet and lengths extending from 0 to 22 feet beyond retarder entrance and exit. Two of the 12 foot high barriers were also tested with a 1 foot inward projecting acoustical panel lip along the top. It was found that the absorptive barriers reduced retarder noise from a few decibels inside the barriers to as much as 25 decibels at 100 feet from the retarder on the system centerline perpendicular to the tracks. Reflective barriers increased noise inside the barriers and at points outside, but near open ends of, the barriers; and reflective barrier noise reduction at 100 feet on the perpendicular centerline was limited to about 16 decibels. Retarder noise was concentrated in a frequency range between 2 and 3 kilohertz. The analytical study presented provides details on the role of observer location as well as the various aspects of barrier configuration.

  • Supplemental Notes:
    • Prepared in cooperation with Industrial Acoustics Co., Inc., Bronx, NY.
  • Corporate Authors:

    Burlington Northern, Incorporated

    176 East Fifth Street
    St Paul, MN  United States  55101

    Industrial Acoustics Company, Incorporated

    1160 Commerce Avenue
    Bronx, NY  United States  10462

    Transportation Systems Center

    55 Broadway, Kendall Square
    Cambridge, MA  United States  02142

    National Highway Traffic Safety Administration

    Office of Research and Development, 1200 New Jersey Avenue, SE
    Washington, DC  United States  20590
  • Authors:
    • Morgan, J A
    • Ingard, U
  • Publication Date: 1979-5

Media Info

  • Pagination: 93 p.

Subject/Index Terms

Filing Info

  • Accession Number: 00198279
  • Record Type: Publication
  • Source Agency: National Technical Information Service
  • Report/Paper Numbers: DOT-TSC-NHTSA-79-35 Final Rpt.
  • Contract Numbers: DOT-TSC-1035
  • Files: NTIS, TRIS, USDOT
  • Created Date: Sep 29 1979 12:00AM