Studies on Elastic Properties of Recycled Concrete by Micromechanical Modeling

Abstract

Understanding the behavior of recycled aggregate concrete (RAC) requires a multiscale analysis to take into account the influence of new particles, the recycled aggregates (RA), in their preparation The overall behavior of recycled aggregate concrete is obtained by a three step homogenization strategy. Several analytical homogenization methods will be used in this work. The effective properties of the recycled aggregates are at the first step determined using the new model named General and Explicit Eshelby Estimation (GEEE) allowing to get the equivalent inclusion properties. The microstructure of the multiphase concrete is then decomposed into several grains. Each grain containing an inclusion family of the same orientation and shape is homogenized by any analytical and efficient homogenization scheme. The equivalent recycled aggregate concrete is finally obtained from homogenized grains by the Voigt model or by the self-consistent scheme. Numerical simulation for different orientation configurations of the equivalent recycled aggregates (random or aligned) were analyzed with taking into account the influence of the interface zone appearing between different phases. The numerical results obtained by the homogenization approach compared with the experimental results from the literature show the accuracy of current multiscale modelling to reproduce the elastic behavior of the recycled aggregate concrete.