Conclusion of the long-term evaluation of open-grade asphalt for the reduction of traffic noise: Interstate 80 (I-80) Davis Project

摘要

In 1998, the California Department of Transportation (Caltrans) initiated a 10-year study to evaluate the long-term acoustical performance of a section of open-graded asphalt concrete (OGAC) installed on a high-volume, multilane portion of Interstate 80 (I-80) near Davis, California. Noise evaluation of the OGAC pavement was conducted using two types of measurements: 1) the continuous flow traffic time integrated method (CTIM) of measuring traffic noise levels at locations adjacent to the roadway; and 2) the on-board sound intensity (OBSI) method of measuring tire-pavement noise close to the tire-pavement interface. Through 2008, measurements were conducted three times per year, resulting in a total of more than 275 hours of noise monitoring and generating an extensive data set. Following the initial 10-year study, testing was also conducted in June 2009, October 2010, July 2012, and June 2014. The results of these measurements through the final year of 2014 are presented along with a comparison of the OBSI and wayside data.