Development of self-consolidating concretes based on recycled aggregates: Effect of parent concrete strength

Abstract

Self-consolidating concrete is a recent type of highly fluid concrete. The high paste concentration ensures excellent rheological behavior. Concrete includes can be selected with durability aims in mind, considering the severe conditions to which the concrete will be exposed. However, the irregularity of recycled aggregates (initial properties unknown from the old concrete) leads to a need for more knowledge of durability indicators. This research is an experimental evaluation of the characteristics of SCC made with recycled aggregates and sand whose initial parent concrete strength was specified. Three ranges of parent concrete strength were chosen (20 to 30 MPa, 35 to 45 MPa, and above 50 MPa). The main objective is to study the effect of introducing recycled concrete aggregates on the mechanical behavior and durability of SCC (total immersion in water and capillary absorption). The test specimens were analyzed after 28 days of curing. The findings demonstrate increased durability and mechanical behavior were achieved using recycled aggregates with high strength in the parent concrete. However, the mechanical strength and durability of SCCs are reduced when recycled concrete aggregates with low parent concrete strength (20 to 30 MPa) are used in the mix.