A one-mile experimental bituminous surface overlay was placed in October 1987 on State Route 3 in Lawrence County, Kentucky. The experimental section utilized bottom ash aggregate from the Kentucky Power Company's Big Sandy Power Plant, near Louisa, Kentucky. Bottom ashes are generally angular and have very porous surfaces. Approximately 539 tons of the experimental bituminous surface material, containing 40 percent bottom ash (dry weight), were placed. Reported herein are results of laboratory tests and performance evaluations of the experimental surface mixture.

Performance of the experimental bottom ash surface has been excellent. Skid resistance tests indicate the surface is highly skid resistant. Bottom ash represents a large potential source of high-friction, nonpolishing aggregate that may be successfully substituted for a portion of the coarse aggregate in a bituminous surface mixture.

Report Date


Report Number


Digital Object Identifier



The contents of this report reflect the views of the author, who is 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 and are not to be considered as endorsements.