A GUIDE TO DETERMINING THE OPTIMAL GRADATION OF CONCRETE AGGREGATES

The proportioning of fine and coarse aggregates in the concrete mix has an important effect on the properties of both fresh and hardened concrete. This guide provides a means of determining the optimal gradation of fine and coarse aggregates for use in the concrete mix using a set of tables. The tables are based on a computer model for the theoretical packing of spherical particles which takes into account their size and specific gravity. Use of these tables in conjunction with the American Concrete Institute's ACI Standard Practice 211.1 should help produce a more workable mix, and a better consolidated hardened concrete with decreased permeability and improved durability.