Development and optimization of geopolymer-based artificial angular coarse aggregate using cut-blade mechanism

This research introduces a novel approach to developing geopolymer-based artificial coarse aggregate using a cut-blade mechanism, providing an innovative approach to traditional aggregate. A modified concrete drum mixer equipped with additional cutting blades was employed to produce angular aggregates with consistent particle sizes ranging from 10 mm to 20 mm with rough surface texture. Compared to conventional techniques, this method ensures a more uniform aggregate shape, enhancing its mechanical interlocking properties in construction applications. The experimental results demonstrated abrasion values between (13.2% to 31.5%), impact value test (9.8% to 21.6%), water absorption rates of (2.62% to 4.2%), and specific gravity values ranging from (1.18 to 2.2). To further optimize the alkali activator dosage, a mathematical model was developed using the ANOVA test and Response surface methodology (RSM), achieving high regression predictive accuracy with R 2 values > 0.93. The model demonstrated optimal results between experimental results and predicted results for specific gravity, impact value, abrasion value, and water absorption. Microstructural analysis via Scanning electron microscopy (SEM) reveals optimal pore distribution inside aggregates, while X-ray Fluorescence identifies significant intensities of Quartz, Ettringite, and calcium silicate hydrate gel. Overall, this research not only demonstrates the technical feasibility of producing high-performance artificial aggregate from waste materials but also underscores its potential to mitigate environmental impacts and promote sustainable construction practices.