In 2009, Ministry of Transportation of Ontario (MTO) initiated a study on the effectiveness of using different asphalt mix types in reducing noise arising from the tire-pavement interaction at the source. Five trial asphalt sections were constructed in October 2009 on Highway 405 in the Niagara Region.
In 2015, MTO Eastern Region also conducted a quiet concrete pavement study to compare NGCS (Next Generation Concrete Surface) pavement with several conventional transversely tined concrete pavements. On Board Sound Intensity (OBSI) measurements were conducted according to AASHTO TP76-12 on a total of nine (9) sections of Highways 115, 417, 401 and 410.
In 2022, MTO Pavements Section undertook another OBSI noise study on seven (7) test sections along Highways 401, 402 and 404 located in Western and Central Regions. These studies generally used asphalt mix sections as controls, consisting of Superpave 12.5 FC2 or SMA 12.5 (Stone Mastic Asphalt) asphalt surface mixes. The remaining sections were concrete sections of varying ages with different surface texture treatments such as grooving, tining or a combination thereof.
From the studies conducted by the ministry, the development of quiet pavement alternatives can provide a more cost-effective solution to address noise pollution in urban areas than use of noise barriers. The studies have shown that pavements with different textures provide different noise reduction effects and open graded asphalt mixes and longitudinally grooved concrete pavements have shown the best long-term performance in sound mitigation. This paper presents the findings from the above noted pavement noise studies conducted by MTO between 2009 and 2022. Longitudinal grooved concrete pavement and open graded asphalt pavement textures are found to provide the best tire-pavement noise mitigation at the source for the flexible and rigid pavement, respectively. It is recommended to upgrade the traffic noise model (TNM) developed by Federal Highway Administration (FHWA) that MTO is currently using to account for new pavement textures, which is essential for accurate environmental screening of road projects.
