Utilization of Rice Husk Ash and Demolished Waste for Sustainable Concrete

In the current age of rapid development and technological advancement, the generation of waste materials is escalating, while the availability of natural resources continues to diminish. This scenario highlights the critical importance of reusing waste materials effectively. In the construction sector, debris from demolished structures presents an opportunity for reuse, particularly in smaller-scale constructions and roadwork applications. This research investigates the incorporation of demolished concrete aggregates, rice husk ash (RHA), and chemical admixtures in varying proportions within M30 grade concrete. Natural coarse aggregates were partially replaced with recycled demolition aggregates at replacement levels of 10%, 20%, 30%, 40%, and 50%. Additionally, ground granulated blast furnace slag (GGBS) was used as a partial substitute for cement at 0%, 5%, 10%, 15%, 20%, and 25%, while a water-reducing admixture was included at 2% of the cement weight. The study involved conducting physical tests such as workability, toughness, and abrasion resistance. Concrete cubes were cast and tested to determine compressive strength at both 7 and 28 days, alongside flexural strength assessments at 28 days.