Analysis of the behavior of mass concrete with the addition of carbon nanofibers (CNFs) when exposed to fire

Abstract

Due to the importance of concrete as a structural material and the pathologies that can be achieved by reinforced concrete structures when they are subjected to the action of fire both at the level of resistance and deformation, in this research we study the mechanical behavior of mass concrete with the addition of carbon nanofibers (CNFs) when exposed to the action of fire, in order to determine the improvements that this type of addition produces in concrete. To achieve this objective, compression break tests have been carried out on cylindrical concrete specimens incorporating CNFs. From the analysis of results, it can be concluded that the residual resistant capacity of concrete with the addition of 1% of CNFs by weight of cement subjected to the direct action of fire, is greater than that of concrete without additions, not obtaining better results, if the addition of CNFs increases to 2%. The addition of 1% of CNFs has not influenced the temperatures reached in the concrete, but produces a more homogeneous cooling and that the paste-aggregate bond is maintained despite thermal aggression, which decreases the spalling effect.