Keywords

Abstract

Plastic concrete;

 Slump test;

 Mixing design;

 Carbon based materials

Incorporating carbon-based materials, particularly carbon nanotubes (CNTs), into the initial composition of plastic concrete has demonstrated potential in enhancing properties such as particle cohesion and resistance to corrosive environments. This study investigates the influence of CNTs on the mechanical and durability characteristics of concrete through 24 distinct mix designs, all maintaining a constant water-to-cement ratio of 0.5. The CNT content varied at levels of 5%, 10%, 15%, and 20% by weight of cement. For each mix, six cylindrical specimens (15 × 30 cm) and three cubic specimens (15 × 15 × 15 cm) were prepared for evaluating compressive strength, permeability, and modulus of elasticity. The experimental results indicate that under a fixed water-to-cement ratio, increasing the cement content significantly raises the viscosity of the concrete mixture, often resulting in a slurry-like consistency. Conversely, an increase in bentonite content at a fixed water-to-cement ratio enhanced fluidity, thereby increasing the slump of fresh concrete. However, this fluidity caused segregation of aggregate particles during placement into molds, adversely affecting compressive strength. Furthermore, for designs containing 30 kg of bentonite, the water absorption and particle segregation rates increased with a higher cement content. In contrast, as the bentonite content increased from 30 kg to 60 kg, water absorption at the concrete surface and particle segregation decreased, suggesting improved homogeneity and resistance to moisture penetration. These findings provide insights into optimizing the composition of plastic concrete containing CNTs and bentonite for enhanced performance in structural applications.

© 2024 MIM Research Group. All rights reserved.