Thermal performance of radiant floor heating systems concrete slabs

This paper investigates the application of recycled steel powder as an additive in concrete to increase the thermal properties of radiant floor heating systems. The project aimed to increase the efficiencies of thermal conductivities, allowing radiant heat to produce higher energy-efficient outputs for heating. Thermocouple readings measured lower temperatures with similar heating conditions as a standard mix slab due to heat transfer occurring evenly through a large surface area, thus transferring heat to the air at faster rates. The tests were completed by casting two 400 × 400 × 200 mm (width × length × depth) slabs enclosing radiant heating pipes. Water was pumped at 40 and 60°C through the pipes. The temperature was recorded at various positions throughout the slab that would allow the multi-layered cylinder approach to analyse the rate of heat transfer, and calculate the efficiency of the heat transfer. The crushing strength of the proposed mix using steel powder replacement is shown to be reduced by 26% when a mix with 12.4% of steel powder is used. Contrary to the original hypothesis of this research, the investigation found rates of heat transfer during the heating stage were 3% lower for the mix containing steel powder compared to the standard mix.