Abstract- The construction industry is one of the largest consumers of natural resources, particularly coarse and fine aggregates, and at the same time it generates a massive amount of construction and demolition (C&D) waste. Rapid urbanization, redevelopment activities, and infrastructure expansion have increased the volume of demolished concrete waste, which is commonly disposed of in landfills or dumped in open areas. This practice creates severe environmental issues such as land pollution, dust generation, and depletion of natural aggregate sources. Therefore, the reuse of recycled aggregate (RA) obtained from demolished concrete is gaining significant attention as an eco-friendly and sustainable alternative to natural aggregate (NA). Recycled aggregate concrete (RAC) has emerged as a promising material in sustainable construction, offering the dual advantage of reducing C&D waste disposal and conserving natural resources. This review paper presents a detailed evaluation of experimental investigations conducted on recycled aggregate concrete over the last decade. The paper discusses the influence of recycled coarse aggregates (RCA), recycled fine aggregates (RFA), and recycled powders (RP) on the fresh properties, mechanical properties, durability performance, and structural behavior of concrete. It highlights the findings of major studies related to compressive strength, tensile strength, flexural strength, modulus of elasticity, workability, density, water absorption, shrinkage, permeability, frost resistance, and chloride penetration. Additionally, the review includes innovative treatment and improvement techniques such as heating treatment, ball milling method, slurry mixing approach, nano-silica incorporation, mineral admixtures (fly ash, silica fume, slag, alccofine), and fiber reinforcement. The study also identifies key research gaps such as limited durability studies in Indian climatic conditions, lack of standardized mix design methodology for RAC, insufficient dynamic structural performance analysis, and limited field-scale applications. Finally, this review concludes that recycled aggregates can be effectively used in concrete production, particularly at partial replacement levels (20–40%) without significant loss of strength. With suitable treatments and the use of supplementary cementitious materials, higher replacement levels can also be achieved while maintaining adequate performance. Thus, RAC has strong potential for sustainable and economical construction practices.
Kamle et al. (Fri,) studied this question.