Identifying the best mixing procedure practice for ready-mix concrete plant production of carbon fibre reinforced electrically conductive concrete

Abstract

ABSTRACT Electrically-conductive concrete (ECON) can generate heat for melting pavement ice if an electrical voltage is applied, and this ECON-heated pavement system (HPS) is a viable alternative to the traditional snow removal methods. This study aimed at determining mixture proportions and procedures suitable for ready-mix concrete-plant-produced carbon fibre (CF)-reinforced ECON. Trial batches ECON production involving five different mixture proportions and procedures were performed at a ready-mix concrete plant. Study results suggest that CF begins to degrade with increased mixing time. A twelve-minute mixing time from the start of loading CF onto the mixer until the end produced the best-performing ECON, with an electrical resistivity of 224 Ω-cm and a heat-generation rate of 2°C/min. Scanning electron microscopic (SEM) image analysis shows that CF remained as blobs of fibre instead of being uniformly dispersed. Further research is recommended to find an efficient way of separating individual CF from the blobs and ensuring uniform CF dispersion to reduce the dosage rate and construction cost of ECON.