Researchers at Purdue University have developed a 12 foot diameter, 38,000 pound machine that allows them to test various concrete compositions and tyre types in the search for quieter pavements.
The device consists of curved sections of pavement that fit together to form a ring, over which two tyres are run at various speeds. Microphones and others sensors record noise and other data.
The Purdue developed machine is the only one of its type. Other devices use stationary tyres ride on moving beds of pavement, or require the towing of a tyre behind a vehicle. Another advantage of the Purdue device is the ability to control test conditions such as acoustics and weather.
So far the researchers have tested 3 types of concrete and four types of tyres. Despite the different nature and construction of the tyres, little difference was observed regarding noise generated by the tyres. The different pavement types produced a more significant difference, with the porous material producing less noise then the textured or smooth surfaces.
While they were unable to explain the cause of this behaviour, they do intend to investigate the interface between the tyre and pavement to test a number of theories.
Source: Purdue University
Posted April, 2003