| Absolutely. Basically the volume of sound emitted increases in proportion to the tyre size and speed, and also is affected by its tread pattern. In short, the road noise from tyres is due to air being compressed by the tread and then released again. It's basically a constant rolling version of clapping your hands. Modern formulations of tarmac are designed to settle with air channels (called voidage) to provide an exhaust for that air, significantly reducing the volume. If you want more information on a couple of types, look up stone-matrix asphalt or open-graded friction course. Concrete on the other hand is notoriously poor for sound reduction, because the surface is so much smoother. As a rough rule of thumb, quietened surfaces come in at 6-9db lower than a comparable non-quietened surface. ARFC is another kind, made of recycled rubber mixed as a secondary aggregate. It's commonly used as a quiet and long lasting surface in parts of the US, and has the advantage of being a good product for using up waste tyres. In the UK we have different compounds, which do similar things. The M4 between Swindon and Bristol is a particular treat to drive on acoustically. Undersurface is potentially an issue too. For example, concrete surfaced in mono-aggregate based tarmac has a tendency to resonate and "sing". Concrete with undulations does the same, though for different reasons. I could go on for some time but it's kinda dull. |
I find civil engineering is often quite interesting, because the tradeoffs and issues can be surprisingly inobvious.