TOWARD THE USE OF PHASE CHANGE MATERIALS (PCM) IN CONCRETE PAVEMENTS: EVALUATION OF THERMAL PROPERTIES OF PCM

Abstract

Phase change materials (PCM) have the potential to be used to store thermal energy from ambient, solar or applied sources. Due to the PCM’s high heat of fusion, the stored energy can be released during cooling (i.e., during a freezing/icing event), thereby delaying or preventing ice formation. This can help to eliminate or decrease the deicing salt demand to melt ice or snow on the surface of concrete pavements. Deicing salts can cause premature deteriorations in concrete pavement by physical or chemical damage. The research team, as a part of a Federal Aviation Administration (FAA) study through the PEGASAS center, has begun to investigate the potential use of PCM in concrete pavements to reduce ice formation and snow accumulation on concrete pavements. As a first step,it has been attempted in this paper to evaluate thermal properties of different PCMs made of fatty acids and methyl esters. The temperature of the liquid-solid phase transition is determined and the latent heat absorbed or released during the phase change is measured using a low temperature differential scanning calorimeter (LT-DSC) for each PCM. This work begins to discuss how the thermal properties can be changed by altering the compositions in order to remain in the desired temperature range. Additionally, this paper discusses how the use of PCM in concrete can be increased by changing absorption technique or lightweight aggregate (LWA) type.