Extending aggregate resources: a symposium. Hotaling WW Jr., ed. Philadelphia, PA: American Society for Testing and Materials (ASTM), ASTM STP 774 1982 :196-212
Through a cooperative program between the Bureau of Mines Tuscaloosa Research Center and the Federal Highway Administration, ceramic aggregates having high wear resistance and polish resistance were developed. Three hundred aggregate compositions, incorporating a variety of low-cost "waste" materials, were evaluated over a 30- month period. Aggregates are produced using conventional ceramic processing techniques and fired at temperatures ranging from 900 deg. to 1,500 deg. C. British wheel and Los Angeles abrasion tests were used for initial screening of the aggregates. These data, in addition to raw materials costs, availability, and energy requirements, were used to select nine compositions for circular track tests at Maryland and North Carolina highway department facilities. Economic evaluations showed that present production costs, based on a 1,000-ton-per-day operation, ranged from $10 to $120 per ton of material produced. Guyana bauxite was used as a standard, and several of the selected compositions developed surpassed the bauxite in performance and were lower in cost.