Investigation of physical and mechanical properties of nanocarbon black-added lightweight UHPC

Abstract

The high specific density of concrete significantly increases the dead load in buildings. Using pumice, which is a volcanic material, as an aggregate in concrete decreases the concrete's density. However, pumice causes a decrease in the mechanical properties of concrete owing to its porous structure. The improvement of the mechanical properties of concrete can provide material savings by reducing the cross-sections of the structural elements to be used in buildings. Ultra-high-performance concrete, which has been an important subject of studies in recent years, is an important construction material for civil engineering. In this study, the physical and mechanical properties of lightweight ultra-high-performance concrete (LW-UHPC) with pumice additive were investigated. Nanocarbon black was added to the mixture as 5, 10 and 15% of the cement weight. Significant increases were observed in the mechanical properties of nanocarbon black-added concrete. The addition of nanocarbon black to concrete at a certain ratio increased the compressive strength and flexural strength of concrete by 9.9% and 10.6%, respectively. In addition, it was observed that the sulfate resistance increased in direct proportion to the increase in the amount of nanocarbon black.