Use of Optimized Aggregate Gradations and Dust-of-Fracture Mineral Filler for Concrete Applications

Abstract

Many proportioning methods exist to help the designer achieve a well-graded, or optimized aggregate gradation in the concrete industry, but not all are effective. The Shilstone Method and percent retained chart have been shown in previous research to enhance the fresh and hardened states of concrete, while also yielding more economical results. These proportioning methods were studied during this research, and found to improve the workability of concrete. In addition, the diminishing supply of natural fine aggregate throughout the country has given rise to the use of manufactured fine aggregate in its place. However, this material has been thought to cause adverse effects on concrete performance, resulting in standard specifications limiting its use and the build-up of dust-of-fracture mineral filler in aggregate quarries. The parent aggregate used to produce the manufactured fine aggregate during this research was dolomitic limestone. This research has found this material to be non-detrimental to the concrete performance with the use of water-reducing admixtures.