Carbon Fiber-Reinforced Asphalt Concrete: An Investigation of Some Electrical and Mechanical Properties

Abstract

Asphalt concrete is a composite material that is extensively used in the construction of highways, airport runways and parking lots. Riding comfort, durability and water resistance are some of the driving mechanical characteristics making it the most preferred choice in the pavement industry. Multifunctional materials have the simultaneous ability to exhibit non-structural functions apart from their regular structural functions. Structural materials can be designed multifunctional by integrating electrical, magnetic, optical, and possibly other functionalities that exhibit advantages beyond the sum of the individual capabilities. Asphalt concrete has the potential of being used as a multifunctional material by controlling its electrical conductivity. Asphalt concrete, by nature, is a non-conductive composite material, but its conductivity can be improved by using conductive materials. The method of inclusion of a conductive filler within the asphalt concrete matrix and its percolation threshold are the factors of interest within this work. The study of the effect of inclusion of the conductive material on the mechanical properties of the hot-asphalt concrete mixtures is another goal of the present work. The results showed that the incorporation of carbon fibers (CFs) within the dense graded asphalt concrete mixtures can enhance their mechanical and electrical properties. The embedding of only 1.5% CFs by volume of mixture improved the stability, IDT and electrical resistivity by 72%, 20% and more than nine orders, respectively. Accordingly, 1.5% CFs represent the percolation threshold of all of the studied properties.