APPLICATION AND FINDINGS OF TSC NOISE PREDICTION METHODOLOGY

The DOT-TSC-FHWA-72-1 Noise Prediction Program has proved to be a useful design tool within certain limits. The program has been adapted to the IBM 370 computer system, and the resultant input and output display modifications have improved the overall utility and afforded a means to quantitatively assess various traffic noise situations. As a design measure, the methodology is responsive to traffic flow volume changes, roadway geometrics, and topographical variations. Experience has also shown that the program produces considerable inaccuracy when utilized during the preliminary stages of project development. Major problem areas have been concerned with the consideration of traffic flow and capacity, the inability in certain situations to accurately account for noise attenuation resulting from natural and artifical barriers, and the inconsistencies between measured and predicted noise level data. Field investigations reveal that the comparative results were poor with the 87.0 dBA heavy-duty-vehicle spectrum and 3.0 dBA drop-off rate. The margin of error for this particular pair of variables is shown to be 8.8 dBA plus or minus 1.8 dBA at 200 ft. from the roadway. All of the test data clearly support the use of the 4.5 dBA per doubling of distance drop-off rate for better predictive accuracy with the TSC Program.

Media Info

  • Features: Figures; Tables;
  • Pagination: p. 41-48
  • Serial:

Subject/Index Terms

Filing Info

  • Accession Number: 00131399
  • Record Type: Publication
  • Files: TRIS, TRB
  • Created Date: May 14 1976 12:00AM