Traditionally, aggregate is divided into arbitrary fine- and coarse-size ranges. There is a movement within the industry to view aggregate grading as a continuum. Proponents believe that a new approach is needed because aggregates may contribute to construction problems and lack of durability, many aggregates lack particles in the mid-range sizes, and there is potential for great variation even within ASTM limits. Until owners are willing to pay for extra time, material and plant equipment, there will probably be little change.
KEYWORDS: aggregate, gradation, process control