Meso-Scale Prediction of Insulating Mortar Thermal Properties

The paper concerns the application of an homogenization technique at the meso-scale, previously developed by the authors for the prediction of the mechanical properties of concrete-like materials, to insulating mortar. The numerical description of the meso-scale of the heterogeneous material and the determination of the heat flux is attained by using a pseudo-random method that allocates at each Gauss point of the RVE finite element discretization a specific phase of the mixture, depending on the volume fractions of the components. Therefore, the model does not consider the physical size of the components. The mesh independency is quickly obtained just by means of relatively coarse meshes of the RVE. Moreover, the randomness of the generation of the micro structure does not affect the overall properties of the mixture. Each pase is characterized by its own thermal properties. The equivalent thermal conductivity of the composite is accurately predicted. The results are compared with experimental measures and with literature data.