INVESTIGATING THE TENSILE STRENGTH OF CONCRETE INCOOPERATING RICE HUSK ASH

Abstract

Concrete is the most common material used in modern construction, but its reliance on cement has created both environmental and economic concerns. Cement production is a major source of carbon emissions, and with the rising cost of raw materials, there is a growing need to find alternatives that are both sustainable and practical. One promising option is rice husk ash (RHA), an agricultural by-product that is rich in silica and has the ability to improve the performance of concrete when used as a supplementary material. This study set out to investigate how replacing cement with RHA, in proportions ranging from 1% to 25%, affects the tensile strength of concrete. A series of mixes were prepared, cured under standard conditions, and then tested using the splitting tensile strength method. The results showed a clear trend: small to moderate amounts of RHA, particularly between 6% and 15%, led to an improvement in tensile strength compared with normal concrete. At these levels, RHA contributed to a denser microstructure and stronger bonding within the concrete matrix through pozzolanic reactions. However, when the replacement level rose above 20%, the tensile strength began to drop, mainly because of reduced cement content and lower hydration activity. The findings are consistent with recent research highlighting how agricultural wastes can make concrete both stronger and more environmentally friendly. Overall, this study demonstrates that using RHA in carefully controlled amounts can reduce cement consumption, lower construction costs, and at the same time enhance the tensile performance of concrete. This makes RHA an attractive material for sustainable infrastructure development, especially in regions where rice production is common and husk disposal poses environmental challenges.