Recycled Concrete Aggregate Classification Based on Quality Parameters and Performance

National/international standards assign the physical and mechanical properties of natural aggregate (NA) to predict the specified properties of natural aggregate concrete (NAC). Physical and mechanical properties of NA such as water absorption, specific gravity, crushing values, impact values, and abrasion values are considered quality parameters for its classification. These properties of natural aggregate determine the performance of concrete and are therefore considered essential parameters in classification. In the same way, classification of recycled concrete aggregate (RCA) is crucial to their use in preparing RAC mixes. The classification may result in the extensive use of RCA as per the requirements. Only physical properties are considered when classifying RCA based on its quality in a few publications. These classifications are not specific because they consider a wide range of variations in the physical properties, and do not consider the mechanical properties of RCA. Consequently, it is not possible to predict RAC properties using these types of classification. In this study, RCA has been classified into four quality categories based on its quality: high quality, medium quality (MQ), low quality (LQ), and poor quality. To validate the classification corresponding to each quality class of RCA, the compressive strength, split tensile strength, flexural strength, bond strength, modulus of elasticity, fracture energy, drying shrinkage, rapid chloride-ion penetration, and sorptivity of RAC are compared based on literature data. There is a strong correlation between RCA quality and RAC performance. Compared to NAC, RAC consisting of LQ and MQ types of RCAs has approximately 40% and 20% less mechanical strength and durability. The performance of RAC is closer to NAC for the high-quality class of RCA. The abrasion values of RCA appear to be the most interesting and essential parameter after analyzing it according to its quality classification. As RCA abrasion value reduces, water absorption, specific gravity, impact value, and crushing value improve.