Long-term behaviour of reinforced beams made with natural or recycled aggregate concrete and high-volume fly ash concrete

Abstract Six simply supported reinforced concrete beams were tested under sustained loads for 450 days. The beams were made from natural aggregate concrete (NAC), recycled aggregate concrete (RAC) and high-volume fly ash concrete (HVFAC); two beams were made from each concrete and loaded after 7 and 28 days. On the beams, deflections, cracking and strains were measured while concrete specimens were used to determine physical-mechanical properties of concretes and measure shrinkage and creep. Results showed similar increases in deflections relative to initial deflections for all six beams. The results are also compared with code predictions and with existing results in literature.