Microstructure-guided design of functional cementitious materials for grid-interactive efficient buildings (GEB)
发布时间:2020-06-29 浏览次数:
Micro- and nano-sized hollow and core-shell particles (CSPs) have attracted tremendous interests in developing functional cementitious composites and concretes. In this presentation, a microstructure guided approach is developed to predict thermal and elastic properties of cementitious composites containing core-shell and hollow micro-particles. The model follows a two-stage homogenization process – CSP inclusions together with their surrounding interfacial transition zone (ITZ) are first treated as equivalent solid particles, and then the homogenized properties of composite system is obtained using numerical (i.e., finite element) or analytical (Mori-Tanaka) approaches. The numerical model, validated by experimental results, is then used to elucidate the relationship between the effective thermal conductivity and effective elastic moduli for cementitious composites containing CSP additives with different shell materials, particle sizes, and volume concentrations etc. The results show that CSP particle size (or relative shell thickness), volume fraction, shell property, and the size of ITZ have significant impacts on the effective thermal and elastic properties of cementitious composites; whereas the particle size distribution pattern has relatively minor influence. Lastly, an application of this method is introduced to design cementitious composites containing large volume loading of phase change materials (PCM) for thermal energy storage (TES).