California–Denmark Study on Acoustic Aging of Road Pavements

Abstract

Knowledge of acoustic aging of road pavements is needed by road administrators when developing policies and strategies for noise abatement. It is important to know how noise-reducing pavements, as well as pavements without such acoustic properties, perform over time. Methods such as the American traffic noise model method or the Nordic NORD2000 method use acoustic aging for accuracy in predicting noise. Noise performance models for road pavements are necessary if noise is to be integrated as an active parameter in pavement management systems. This paper contributes to ongoing international development in the field of acoustic aging by performing a comprehensive analysis of results from four Californian and Danish long-time noise measurement studies on asphalt pavements. There is not much information on which changes in the surface structure cause an increase in noise in the period between when the bitumen film is worn off and when the pavement begins to deteriorate with distresses such as raveling, cracking, and so forth. This study analyzes and compares trends in the development of noise over time. The development of the noise spectra is also analyzed. The increase of noise has normally been analyzed in relation to the age of pavements. The traffic load and an artificial indicator, defined as the change of noise predicted as a combination of actual physical age and traffic load, are investigated.