Study on Strength and Durability Characteristics of Recycled Aggregate Used in Different Grades of Concrete

In this study we investigate the use of recycled coarse aggregate -sourced from a construction & demolition waste processing plant- as a sustainable and eco-friendly material in concrete production. Focus of this study was to develop high-strength concrete using waste materials by replacing the coarse aggregate, fine aggregate and cement with recycled coarse aggregate, robo sand and Ground Granulated Blast Furnace Slag (GGBS) respectively. To achieve better results strength and durability, we designed three concrete mixes viz Mix A, B and C with a respective target strength of 20, 40 and 60 MPa. The corresponding mixes were prepared and tested at the age of 7 and 28 days of curing. Compressive strength for the three mixes exhibits 22, 40 and 61 MPa, which was observed to have achieved target strength within 28 days which may be due to the formation of denser microstructure. Further it leads to offer phenomenal resistance to sorpitivity and permeability of acids into the concrete. Though the recycled aggregate concrete offered mechanical and durability properties on par with natural aggregate concrete, its ability to preserve the clean nature of conventional materials is compromised. However, clean technologies can be adopted to wash the industrially and domestically available waste materials in order to overcome the aforementioned limitation.