Road traffic noise is a major cause of environmental concern in New Zealand. The effect that the road surface has on noise is the one major influence that the roading authority can control.
International literature and road noise models to date have considered that, for speeds below 60 km/h, tyre/surface noise does not have a significant effect (1–2 dBA) on road noise. Current thought is that a 3 dBA noise level change is just noticeable to most people, which makes the widely observed increases in community annoyance from road resealing hard to explain.
This research investigates the effect that road surface type has on road traffic noise at urban driving speeds (50 km/h) and the consequent effect on community annoyance. It then offers guidance on road surface selection, with regards to noise.
Keywords: asphalt, behavioural disturbance, bitumen, calcined bauxite, Cape seal, chipseal, community annoyance, noise generation component, noise levels, road surface type, slurry seal, spectral content, texture depth, tonal difference, traffic noise.