Mix Design Procedure for Alkali-Activated Slag Concrete Using Particle Packing Theory

Abstract

This paper presents a methodology for designing mix proportions for a targeted compressive strength of alkali-activated slag concrete (AASC) using particle packing theory. Very little information is available on a complete methodology in designing the AASC mix. Ground granulated blast-furnace slag is activated with sodium silicate–based and sodium hydroxide–based alkaline activator solution. Sodium hydroxide concentration, binder content, and the alkaline solution:binder ratio are taken as variables. The aggregates are proportioned using particle packing theory, resulting in fewer voids and a dense concrete mix which hinders the ability of external aggressive chemicals to migrate into the concrete. Results show that the sodium hydroxide concentration and alkaline solution:binder ratio are the most influential parameters on compressive strength and workability of AASC. This paper presents a mix design procedure for AASC with a detailed example.