Correlation of tire wear and friction to texture of concrete pavements

Pavement surface texture significantly contributes to tire wear and tire-pavement friction. Currently available relationships quantify tire wear and tire-pavement friction simply in terms of empirical pavement texture parameters. The objective of this paper is to present correlations with which the tire wear rate and tire-pavement friction on smooth concrete pavements can be predicted using actual texture properties. Using a laboratory tire wear simulator and an aircraft tread-rubber block, a number of wear and friction tests are performed on pavement samples having different fine aggregate sizes. Frequency characteristics of the texture of the pavements are achieved by decomposing the profilometer measurements using the fast Fourier transform technique and constructing power spectral density plots of texture over surface spatial frequency. Then the tire wear rates as well as dry friction and wet friction of the tire-pavement interface are correlated to microtexture and macrotexture components of the texture power spectral density. The developed correlations indicate that both tire wear and dry friction are significantly affected by pavement microtexture. The developed wear correlations can be also useful for predicting the wear index of a pavement based on conventional Mu-meter and grease patch test results. This is illustrated by an example in which the wear index for a concrete runway pavement at Luke Air Force Base, Ariz., is computed using the new relations.