Thermal rehabilitation: Contribution of mortars with incorporation of phase change materials

ABSTRACT The residential sector is sometimes old, with urgent intervention needs. Thus, it is important to rehabilitate buildings from a structural, aesthetic and functional point of view. The thermal rehabilitation is an important opportunity to reach higher levels of energetic performance, reducing the high energetic dependence of the countries. Rehabilitation operations based in the utilization of materials with the capability to store and re-lease energy contribute to obtain more energy efficient buildings. Combining the use of smart materials and renewable energy sources, it is possible to increase the thermal comfort inside the buildings. The main pur-pose of this study was the physical, mechanical and thermal characterization of mortars based in specific binders for rehabilitation with incorporation of phase change materials (PCM). Mortars based in aerial lime and gypsum were studied. For each binder, mortars with and without incorporation of PCM were developed. It was observed that the incorporation of PCM in mortars caused differences in the physical, mechanical and thermal behavior. It was verified a decrease in the flexural and compressive strengths, and an increase in the thermal behavior, reducing the maximum temperature, increasing the minimum temperature and decreasing the heating and cooling needs.

摘要 住宅建筑往往年代久远，亟需开展修缮干预。因此，从结构、美观与功能维度对建筑开展修缮工作具有重要意义。热工修缮是提升建筑能源性能的重要途径，可降低国家居高不下的能源依赖程度。基于具备储放热能力的材料开展的修缮作业，有助于打造更为节能的建筑。将智能材料与可再生能源相结合，可提升建筑内部的热舒适水平。本研究的核心目标是对以专用胶凝材料为基材、掺入相变材料（Phase Change Materials，PCM）的修缮用砂浆开展物理、力学及热工性能表征。研究对象为以气硬性石灰与石膏为基材的砂浆。针对每一种胶凝材料，分别制备了掺入与未掺入PCM的砂浆试样。研究发现，砂浆中掺入PCM会使其物理、力学及热工性能产生显著变化。实验证实，掺入PCM会使砂浆的抗折与抗压强度有所降低，但可改善其热工性能：可降低最高温度、提升最低温度，并减少建筑的采暖与制冷能耗需求。