Effect of Multi walled Carbon Nanotubes on Compressive Behavior of High Strength Concrete at Elevated Temperature for Mass Concreting

Abstract

The need for high-rise buildings has increased in recent years as the population has grown. Hence, high-strength concrete has grown more popular than standard-strength concrete. However, the fundamental problem with high-strength concrete (HSC) is that it undergoes numerous undesired chemical changes and thermal fracture on exposure to high temperatures. This quickly jeopardizes the use of high-strength concrete in structural applications. As a result of these challenges, it is necessary to build more thermally stable structures. So, in order to compensate this issue carbon nanotubes (CNT) are induced in this research. The mechanical properties such as compressive strength, flexural strength stress-strain response, elastic modulus, Compressive toughness, mass loss, as well as detoriation caused by the exposure of elevated temperatures were studied. The analyzed formulation was heated up to 200, 400 ,600 and 800 oC at a heating rate of 5 oC /mint and then tested for residual conditions. Carbon nanotubes (CNTs) modified concrete showed a higher compressive strength, elastic modulus, flexural strength, and compressive toughness as compared to the control specimens. According to the visual inspection modified specimens showed less cracking at higher temperatures. Moreover, the effect of plastering high strength concrete with CNTs showed better strength retention on exposure to fire. Conclusively, utilization of CNTs in high strength concrete is efficient as fire resistance concrete.