Effects of the incorporation of recycled aggregate in the durability of the concrete submitted to freeze-thaw cycles

Recycled concrete aggregates have been extensively studied in recent years. However, the studies that have addressed the use of the recycled aggregate in concrete subjected to freeze-thaw cycles are divergent. Thus, the present work suggests the use of recycled coarse aggregate (RCA), derived from civil construction waste, in concrete as a substitution to the natural coarse aggregate (NCA). To this end, concrete specimens were molded with replacement levels equal to 15%, 25% and 50% of the NCA for RCA, being the specimens evaluated according to the ASTM C 666-15 norm. In addition, the samples were characterized for apparent porosity and density, water absorption by capillarity, axial compression strength and dynamic modulus of elasticity. The use of recycled aggregates proved to be efficient as a possible alternative to the incorporation of air in the concretes, presenting a durability factor at the end of the cycle higher than presented by the reference mixture.