Resilient rail fasteners have received significant attention at the New York City Transit Authority (NYCTA) and the Washington Metropolitan Area Transit Authority (WMATA) as a means for reducing wayside noise from steel stringer and steel box elevated structures and groundborne noise from subways. Noise and vibration data collected at NYCTA and WMATA indicate that noise and vibration reductions are generally small unless very soft resilient fasteners are used. Very soft fasteners providing good low-frequency performance may exhibit poor isolation or amplify structure vibration at frequencies above 200 to 400 Hz because of resonances in the elastomer pad or top plate. Laboratory tests of the forward transfer impedance of resilient rail fasteners indicate that these secondary resonance frequencies are about 600 to 800 Hz for the softest fasteners tested for the NYCTA and WMATA systems. A laboratory test procedure has been developed into an acceptance test procedure for resilient fasteners supplied to the WMATA system as noise-reducing fasteners for either subway or elevated structure use. This procedure represents a substantial change in acceptance test procedures that have heretofore focused on physical properties related to stability and safety of the fasteners. Data are presented illustrating measured noise reductions and laboratory test results.

Media Info

  • Features: Figures; References;
  • Pagination: p. 51-54
  • Monograph Title: Current environmental research in transportation
  • Serial:

Subject/Index Terms

Filing Info

  • Accession Number: 00495461
  • Record Type: Publication
  • ISBN: 0309049512
  • Files: TRIS, TRB
  • Created Date: Jul 31 1990 12:00AM