Mesoscale discrete analysis of mechanical properties of recycled aggregate concrete based on Voronoi mesh

The application of recycled coarse aggregate (RA) to produce recycled aggregate concrete (RAC) requires the investigation of its mechanical properties. From literature review, it is found that the experimental data scatters in large extent and even contradictory results exist. Therefore, numerical tool is an appropriate option to evaluate the mechanical performance of RAC. In this paper, a mesoscale approach is adopted to simulate the compressive and tensile behaviors of RAC with different strength levels of old mortar and new mortar, attachment ratio of old mortar within RA and replacement ratio of RA. The numerical study of RAC is followed by the validation on normal concrete with different shapes of natural coarse aggregate (NA). Then parametric studies on RAC are conducted, based on which an empirical model is proposed to predict the compressive strength of RAC with the above-mentioned factors. Experimental data are also summarized to validate the model, which shows satisfied correlation with the predicted value.