Experimental and theoretical characterization of electrodes on electrical and thermal performance of electrically conductive concrete

Transportation agencies regularly seek innovative, cost-effective, and environmentally-friendly approaches to help manage winter maintenance operations during snow and ice events. The use of an electrically-conductive concrete (ECON) heated pavement system (HPS) is a smart and promising alternative to conventional snow and ice removal methods using de-icing chemicals and snow-removal equipment. ECON is made electrically conductive by introducing conductive agents into the concrete mix and applying electrical current through electrodes embedded in the ECON layer. This study investigates the influence of electrode size and geometry on the resistive heating performance of ECON HPS and identifies the most electrically and thermally-efficient type of electrode through experimental testing and theoretical analysis. Electrode performance was investigated in water, prototype ECON slabs, and through development of a finite-element model, and good agreement was found between the results obtained from these three evaluation methods. A theoretical formulation between thermal performance and electrical and material properties in ECON HPS was first developed. Testing electrodes in water was then found to be a quick, non-destructive, and cost-effective alternative method for monitoring thermal performance of electrodes. Finally, electrode surface contact area was identified as the dominant electrode characteristic with respect to influencing temperature increase. Cost and energy analysis for each electrode type showed that smaller-diameter electrodes exhibited higher cost-effectiveness, and conversely, larger diameter electrodes were found to have higher energy-conversion efficiency. The results of this work will provide guidance for choosing the most cost-effective and optimized type of electrode for design and construction of a large-scale ECON HPS.

Automated summary

This study examines the influence of electrode size and geometry on the resistive heating performance of ECON HPS and identifies the most electrically and thermally-efficient type of electrode through experimental testing and theoretical analysis. It was found that electrode surface contact area plays a significant role in influencing temperature increase, with smaller-diameter electrodes exhibiting higher cost-effectiveness and larger diameter electrodes having higher energy-conversion efficiency.