Noise Impact Analysis Using the Traffic Noise Model (TNM) Comparing Different Pavement Types - Average vs. ARFC

The Arizona Department of Transportation (ADOT) initiated the Quiet Pavement Pilot Program (QPPP) in 2002. Approximately 115 miles of freeways in the Phoenix Metropolitan area were resurfaced with Asphaltic Rubberized Friction Course (ARFC) to provide a smoother ride for motorists and quieter neighborhoods adjacent to the freeways. As part of the ADOT QPPP research efforts, this paper evaluated noise level variations and changes in recommended noise barrier heights by using the Arizona ARFC (AZ-ARFC) pavement-type parameters versus default average pavement-type parameters in the Federal Highway Administration (FHWA) Traffic Noise Model Version 2.5 (TNM 2.5). Three representative projects in the Phoenix Metropolitan area were selected for analysis. It was concluded that by placing Arizona ARFC pavement, an average of 2 dBA noise reduction can be achieved for future unmitigated noise levels. The average barrier height can be lowered by approximately 2 feet from approximately 15 feet to approximately 13 feet