Study on flexural behavior of ultra-high-performance concrete beams using finely ground rice husk ash

This research explores the application of finely ground rice husk ash (RHA), an agricultural waste material, in the production of ultra-high-performance concrete (UHPC). Due to its elevated SiO2 content and small particle size, RHA is considered a potential substitute for silica fume in UHPC mixtures. The study investigates the flexural behavior of UHPC beams using RHA as a replacement for silica fume at replacement levels of 25% and 50%. The flexural behavior relationships, including load-deflection, stress-strain, and crack characteristics, will be determined. The experimental results indicate that UHPC beams reinforced with 10% RHA+10% SF exhibit initial crack loads, yield loads, and maximum loads comparable to the reference UHPC beams. The load-deflection relationship curves of the RHA-incorporated UHPC beams demonstrate greater stiffness than the reference beams during the linear phase. These results were also compared with simulations, showing a high level of consistency. The research findings provide important insights into the potential application of finely ground rice husk ash in UHPC, paving the way for new developments in sustainable and economically efficient construction materials.