The Effect of Finely-Grinded Crushed Brick Powder on Physical and Microstructural Characteristics of Lightweight Concrete

Abstract

The utilization of waste crushed clay brick (CB) in concrete reduces its harmful impacts on the environment as it can be found in many places around the world. This research studies the possibility of using clay brick powder (CBP) as a filler material to produce lightweight concrete as it has been exposed to high temperatures during manufacturing of the bricks, which increases its pozzolanic reactivity. The effect of using an air-entraining agent (AEA) for additional pore formation on concrete performance was evaluated. Eight mixtures were prepared and examined to achieve the research objectives. Concrete flowability, dry density, compressive strength, ultrasonic pulse velocity, thermal conductivity, sorptivity, and porosity were measured. Additionally, scanning electron microscopy, X-ray diffraction, thermo-gravimetric analysis, and mercury intrusion porosimetry were used to analyze the microstructure characteristics of the concrete. The results indicate that the use of CBP as filler material enhances the mechanical and durability characteristics of the concrete. In contrast, adding an AEA has negative effects on concrete’s mechanical and durability properties, but on the other hand, its use enhances the thermal properties of the concrete.