Steel fiber reinforced recycled aggregate geopolymer concrete: A mechanical assessment

Abstract

In this study the mechanical characteristics such as compressive strength and splitting tensile strength of fly ash/slag based steel fiber reinforced geopolymer concrete with and without partial replacement of the recycled coarse aggregate(RCA) have been tested according to the standard procedures and compared. In the study, a total of ten cubic (10cm×10cm×10cm) and ten cylindrical samples (10cm×20cm) were tested to determine compressive performance and splitting tensile strength, respectively, for five different mix designs. The proportion of recycled aggregates considered consists of 10%, 20%, 30%, and 40% of the total coarse aggregate amount. In general, the inclusion of recycled coarse aggregates reduced the engineering properties of geopolymer concrete in comparison to the reference mix prepared without adding RCA. The reduction rate was found to be significant in the case of 30% and 40% replacement of the recycled aggregate. Nevertheless, 10% and 20% caused only a slight reduction in the compressive strength of the resulting concrete matrix. Furthermore, splitting tensile strength of the geopolymer concrete matrix was significantly affected by the replacement of a recycled aggregate percentage of more than 30%. © 2023 AIP Publishing LLC.