This report lists and discusses results of field permeability tests and laboratory shear tests on samples from a construction project on the Western Kentucky Parkway in Caldwell-Hopkins Counties. Approximately 6,500 tons of asphaltic concrete overlay placed on this project failed to meet minimum density requirements.

Field permeability tests were performed and the results showed that in areas where the mat failed to meet density requirements there was very high permeability in those locations.

The laboratory shear tests also showed that there was a direct relationship between shear strength and density. A linear elastic layer stress analysis also indicated that the shear strength of all of the laboratory tests specimens except one was less than the theoretical stresses that would occur under wheel loadings experienced in the field.

It was concluded that the overlay would probably have a shortened service due to the low densities which would possibly cause excessive raveling and rutting. It was recommended the material be removed and replaced.

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The contents of this report reflect the views of the authors, who are responsible for the facts and accuracy of the data presented herein. The contents do not necessarily reflect the official views or policies of the University of Kentucky, the Kentucky Transportation Cabinet, nor the Federal Highway Administration. This report does not constitute a standard, specification, or regulation. The inclusion of manufacturer names or trade names are for identification purposes only and are not to be considered as endorsements.