System Design Improvements of Heated Pavements: Recommendations for Future Projects

Abstract

Many agencies allocate a great deal of resources to clearing infrastructure systems (e.g., roads, bridges, and airports) from ice and snow during winter seasons using traditional snow-removal equipment and application of salt or de-icing chemicals. Using an electrically-conductive concrete (ECON) heated pavement system (HPS) is a cost-effective and environmentally friendly approach to melting ice and snow. ECON is a carbon-fiber-reinforced form of concrete that uses carbon fiber (conductive agent) with low median electrical resistivity to conduct electrical current through the concrete ECON layer through embedded stainless-steel electrodes. The inherent electrical resistance in the concrete generates heat used in the ECON HPS to melt ice and snow on the surface. ECON HPS construction is different from regular concrete construction in using two-lift paving, two different concrete mixes, and embedded stainless-steel electrodes with electrical connections to a power supply. An ECON HPS demonstration project has recently been constructed at the south parking lot of the Iowa Department of Transportation in Ames, Iowa. This project consists of 10 instrumented slabs, and this paper is focused on the ideas for improvement and lessons learned emerged from the full-scale demonstration project with respect to the construction methods the ECON mix design, control system design, electrode, cross slope design, and instrumentation of the concrete pavement system. These improvements in the construction of this unique concrete pavement system are expected to increase future paving quality, ECON HPS performance, and significantly decrease construction time and cost of such systems.