The acoustic effects of diamond grinding Portland cement concrete pavement surfaces

Transversely tyned Portland Cement Concrete (PCC) pavement surfaces generate very high levels of road traffic noise. A couple of years ago it was suggested, largely on the basis of experiences in the USA and Canada, that the introduction of narrow longitudinal grooves to these pavement surfaces would attenuate the noise. The longitudinal grooves would be applied through a process known as diamond grinding. Following that suggestion, diamond grinding was undertaken on several sections of PCC pavement surfaces in rural New South Wales (NSW) and in metropolitan Sydney. The diamond grinding was done for the NSW Roads and Traffic Authority (RTA) on roads under its jurisdiction as part of an ongoing development program. The present paper documents the conduct and outcomes of a series of investigations aimed at determining the acoustic effects of this diamond grinding process. The primary objectives of these investigations were to determine the road traffic noise characteristics of the original pavement surfaces investigated and to determine how these characteristics changed after the diamond grinding process. The outcomes of these investigations demonstrated, contrary to expectation, that the diamond grinding process had little or no effect on the road traffic noise generated on the pavement surfaces studied.