Road to Quiet Neighborhoods in Arizona (05-2566)**
Larry A. Scofield, International Grooving and Grinding Association
Paul Donavan, Illingworth & Rodkin, Inc.

The Arizona Quiet Pavement Pilot Program (QP3) is a $34 million project implemented to reduce highway related traffic noise. This pilot program represents the first time that pavement surface type has been allowed as a noise mitigation strategy on federally funded projects. The program will overlay most of the Phoenix metropolitan area PCCP with one inch of ARFC. As a condition of using pavement type as a mitigation strategy, ADOT developed a ten-year, $2 million research program to evaluate the efficacy of using ARFC. Historically, pavement surface type was not considered a permanent solution due to the change in acoustic properties with time. This research program will evaluate the change in pavement acoustic properties through three means, (1) conventional roadside testing (eg far field measurements), (2) the use of near field measurements, both Close Proximity (CPX) and Sound Intensity (SI), and (3) far field measurements taken within the surrounding neighborhoods. This paper provides an overview of the program development, presents the research conducted to support the decision to overlay the urban freeway, and the status of current research. Particular emphasis is placed on the development and use of near field measurement systems consisting of CPX and SI Preliminary results from the research to date indicate that the near field measurement systems are providing meaningful assessments of pavement acoustic performance and the SI and CPX methods compare favorably. The overlays placed reduce the near field measurement levels between 6 to 11 dBA. Average reductions of 5 dBA occurred in the neighborhoods.