Since about 1948, the performance of natural rock asphalt, used extensively in Kentucky and Indiana, has been plagued by a unique type of scaling in the wheel tracks of each traffic lane. This scaling has been typically an eighth to a quarter of an inch thick and has left the pavements rough and unsightly. In some cases, this phenomen has occurred several times in the same place and has caused much deeper rutting. The general condition is illustrated in a series of photographs attached hereto.
Digital Object Identifier
Havens, James H. and Williams, Ellis G., "Performance of Kentucky (Natural Sandstone) Rock Asphalt" (1955). Kentucky Transportation Center Research Report. 1340.