Analysis by Differential Scanning Calorimetry of concrete modified with microencapsulated phase change materials

In this work, a thermal experimental investigation by Differential Scanning Calorimetry (DSC) of a Portland cement concrete modified with microencapsulated phase change materials labeled “PCM-concrete” is presented. First, the DSC technique was used for the thermal characterization of the micro-PCMs considered in this study. Accordingly, several thermal properties were determined such as the melting and freezing temperatures, the specific heat capacity and the change phase enthalpies. After, concrete mixtures with different PCM amounts were manufactured in laboratory and then the compressive strength was measured. Then, the PCM-concrete thermal performance was studied by DSC. Also, artificial accelerated ageing was performed on the PCM concrete mixtures in order to investigate the PCM stability in the concrete. Next, the thermal properties of the artificial aged PCM-concrete were determined by DSC and compared with the non-aged PCM concrete properties. Finally, the microstructure of the PCM concrete mixtures was analyzed by Scanning Electronic Microscopy (SEM) to check the PCMs state after their incorporation in the concrete. The results highlighted an improvement of the specific heat capacity of the PCM-concrete with the addition of PCMs. A slight loss of the mechanical strength was noted. Also, the thermal storage of PCM-concrete mixtures after the artificial ageing was enhanced with comparison with the reference non-aged one.