Mechanical properties of high-strength mortars with fine recycled concrete aggregates

This study investigated the effect of replacing natural fine aggregate (NFA) or natural sand with fine recycled concrete aggregate (FRCA) on the mechanical properties, including density, compressive strength, and flexural strength, of high-strength cement-based mortar. Several mortar mixtures were produced by adding various FRCAs to the mixture in percentages of replacing 0%, 25%, 50%, 75%, and 100% of NFA content. The dynamic behavior of the recycled mortar under impact loading using a Split–Hopkinson pressure bar (SHPB) was also evaluated. Overall, results showed that the mechanical performance of the recycled mortar decreased with increasing FRCA replacement level. FRCA at ratios of up to 25% exerted minimal adverse effects on the mechanical properties of mortar.