Thermal and mechanical performance of phase change material incorporated concrete pavements

Higher pavement temperature leads to urban heat island (UHI) effect and thermal distresses in concrete pavements. Incorporation of phase change materials (PCM) is one of the prospective ways to reduce this temperature. In this study, two types of PCMs, Organic Mixture 35 (OM 35) and Organic Mixture 42 (OM 42), were introduced through expanded clay aggregates (ECA). As the PCM adversely affects the cement hydration and reduce the mechanical strength of concrete, ECAs were coated with cement paste to avoid leakage. Differential scanning calorimetry (DSC) and thermo-gravimetric analysis (TGA) of PCM impregnated ECA indicated that it can store latent heat at the desired temperature range for pavement applications and are thermally stable up to 196.6°C. From a field demonstartion, it was observed that concrete slabs constructed with OM 35 and OM 42 reduced the maximum pavement surface temperature up to 1.85°C and 2.76°C respectively with respect to the control slab.