Improvement of Electrical Conductivity in Carbon Fiber-Concrete Composites Using Self Consolidating Technology

This paper presents the investigation of the effectiveness of self consolidating technology to improve the dispersion of carbon fibers and, therefore, electrical conductivity in concrete. The reduced working viscosity and void filling abilities of self-consolidating concrete (SCC) will be explored to address the problem of fiber dispersion. The practical results of this exploration will be applied to an electrical self-heating concrete system which uses resistive heating to provide heat to concrete in freezing environments for deicing or snow melting purposes. Resistivity of plain concrete with normal fiber, plain concrete with surfactant treated fiber, and SCC with plain fiber was experimentally determined over sample temperatures ranging from +20°C — –20°C. In all samples, it was observed that as temperature decreases, resistivity increases exponentially. Resistivity was also compared across sample types and carbon fiber composition. It was found that different mixing techniques had significant effects on sample resistivity, though there remain problems to be solved in using long carbon fibers in SCC.