Analysis of Behavior of Concrete With Hybridization of Steel Fibers and Carbon Nanofibers

Abstract

The present study shows an investigation on the mechanical behavior of the compressive strength in mixed fiber reinforced concretes in comparison with traditional concretes. A hybridization of carbon nanofibers (CNFs) in 1% by weight of cement mixed with steel fibers in 1% by weight of cement was made. The specimens were subjected to the compression rupture test to analyze the maximum rupture stress, the maximum deformation and the deformation energy density and contrast the results with a concrete without additions. The thermal conductivity test and scanning electron microscopy (SEM) were also performed. The results show that concrete with hybridization of steel fibers and carbon nanofibers, in percentages of 1% by weight of cement of each fiber, achieves slightly higher average compressive stresses than non-added concrete, but loses ductility once the maximum stress is reached. The thermal conductivity in fiber-hybridized concrete is similar to that of fiberless concrete, not producing the improvement that could be expected by adding fibers from materials with high thermal conductivity. Keywords: hybridization, carbon nanofibers, concrete, steel fibers