Early-age mechanical properties of recycled aggregate concrete

The use of small amounts of recycled concrete aggregates (RCAs) is frequently asked in the precast industry in many European countries to enhance the sustainability of the products. The early age and time-dependent properties of concrete with RCAs, often called recycled aggregate concrete (RAC), are of crucial importance to examine the feasibility of the utilisation of RCAs in precast concrete components. This paper provides a study on the mechanical properties of RAC at early ages, including the compressive strength, the splitting tensile strength and the modulus of elasticity, based on available data in literature and recent test results by the authors. The developments of the mechanical properties of RAC with time are studied. The suitability of the equations given in EN 1992-1-1:2004 (which are developed for conventional concrete) for RAC is also examined.status: publishe