Properties of Concrete Containing Quarry Dust–Fly-Ash Cold-Bonded Aggregates Subjected to Elevated Temperature

Abstract

This paper investigates the possibility of using waste materials such as quarry dust and fly ash in the manufacture of cold-bonded aggregates. The artificial aggregates were prepared by varying the waste quarry dust content between 0% and 75% by weight. Fly ash activated using lime was used as a binder. The comparable strength property was obtained for an aggregate made of 37.5% quarry dust and 62.5% activated fly ash. Hence, the aggregates with this proportion were used to prepare the concrete specimens. The concrete was cast by varying the coarse aggregate replacement ratio of 0%, 25%, 50%, 75%, and 100%. A few specimens were tested without exposure to elevated temperatures, and the remaining specimens were tested after exposure to elevated temperatures. The elevated temperatures of 200°C, 400°C, and 600°C were considered in this study. The strength and durability properties of concrete containing cold-bonded aggregate were investigated. Compressive and tensile strength and modulus of elasticity, mass and strength loss due to acid and sulfate attack, and bulk diffusion tests were carried out. The concrete containing quarry dust–fly-ash (QDFA) aggregate alone exhibited low strength reduction when exposed to elevated temperature. A prediction model for the strength properties of QDFA aggregate concrete was proposed. The study showed that QDFA cold-bonded aggregate is a promising material for green construction.