Influence of the purity of recycled concrete aggregates on the mechanical properties of dry and self-compacting precast concrete

Although different researches have already shown that the creation of concrete with partial replacement of the coarse aggregates by recycled coarse concrete aggregates is feasible with limited effect on the mechanical and durability properties of the concrete, still a lot of questions remain. One of these questions is the influence of the quality of the recycled aggregates. This study takes a closer look at the influence of the purity of the recycled concrete aggregates and its influence on two different precast concrete mixtures: a fast hardening dry mixture used for hollow-core slabs and a self-compacting mixture used for beams and floors. Different parameters which are of importance for precast companies were examined: early age compressive, bending and splitting strength, 28 day compressive and splitting strength and concrete density.status: publishe