Assessment of asphalt concrete acoustic performance in urban streets

Abstract

Geo-referenced close proximity rolling noise and sound absorption measurements are used for acoustical characterization of asphalt concrete surfaces in an urban environment. A close proximity noise map of streets with low speed limits is presented for a reference speed of 50 km/h. Different pavements and pavement conditions, common in urban streets, are analyzed: dense and semidense asphalt concrete, with Spanish denomination D-8 and S-12, respectively, and on the other hand, dense pavement at the end of its service life (D-8(*)). From the acoustics point of view, the most favorable surface, by more than 4 dB(A) compared with the S-12 mix, is the smoothest surface, i.e., the D-8 mix, even though it presents a minor absorption coefficient in normal incidence. Noise levels from dense surfaces (D-8) increase significantly over time, principally due to the appearance of surface defects such as cracks and ruts. Longitudinal variability of the close proximity tire/pavement noise emission and surface homogeneity are also analyzed.

Surface Aging Effect on Tire/Pavement Noise Medium-Term Evolution in a Medium-Size City

“…Nevertheless, tire/pavement noise and profile measurements have been conducted at an average speed of 50 km/h. This paper analyzes some pavement surface characteristics (tire/pavement noise, MPD) measured in recent tests, and compares them with those achieved in previous works [34].…”

“…Nowadays these levels exceed 90.0 dB(A) (except Section 1, where L CPtr, 50 km/h = 89.8 dB(A)). These values are higher than others achieved from conventional mixtures (at 50 km/h) such as AC16 surf S (asphalt concrete) [34] or BBTM 8 mixture (very thin asphalt concrete) and PAC8 (porous asphalt course) [36]. According to the authors, these conventional mixtures were laid, 10 (AC16) and 24 (BBTM and PAC) months before their measurement by means of the close proximity method.…”

“…Figure 8 shows the mean values of L CPtr, 50 km/h noise levels (dB(A)) and MPD (mm), together with the spatial standard deviation of L CPtr, 50 km/h noise levels. The results depicted in this figure include those of the measurement campaigns accomplished in 2008, 2013 and 2015 [34,35].…”

Composites with recycled rubber aggregates: Properties and opportunities in construction

“…The addition of crumb rubber increases pavement service life and stiffness, as well as rutting and cracking resistance [Fontes 2010, López-Moro 2013. Moreover, compared to plain asphalt concrete, tyrerubberised asphalt generates less noise in service conditions [Paje 2008]. Blends of tyre rubber and recycled polyethylene have been used in bitumen blends to obtain better rheological behaviour [Zaman 1995].…”

Noisiness of the Surfaces on Low-Speed Roads

“…One way to reduce the noise level then is applying low-noise surfaces. In some countries, wearing courses of porous asphalt are used on city streets and on low-speed roads [18,19]. At low vehicle speeds, however, these surfaces become clogged in a relatively short period of time, and, after a few years of operation, tire/road noise level on such roads reaches values comparable to the noise level on the standard asphalt concrete (AC) and stone mastic asphalt (SMA) surfaces.…”