A State-of-the-Art Review on Suitability of Rice Husk Ash as a Sustainable Additive for Geotechnical Applications

Amidst the escalating urbanization and burgeoning infrastructural requisites, the imperative of deploying sustainable and efficacious soil stabilization methodologies has been amplified to unparalleled prominence. In particular, using waste materials such as rice husk ash (RHA) for soil stabilization presents -economical and sustainable solutions. RHA is a by-product of the rice milling process. This paper thoroughly reviews the existing research related to soil stabilization using RHA. Studies reviewed herein highlight RHA’s potential as a soil stabilizer due to its high silica content and pozzolanic properties. The effect of RHA on various soil properties, such as Atterberg limits, compaction characteristics, strength, swelling, and durability, are critically reviewed. This paper further discusses the effect of different factors, including RHA’s specific surface area (SSA), its interaction with various soil types, and the influence of the curing period on the overall performance of RHA-stabilized soil. The review also delves into the recent advancements in testing methodologies such as X-Ray Fluorescence (XRF) and Brunauer, Emmett, and Teller (BET) methods for soil and RHA characterization. Current challenges, research gaps, and potential areas for future research are also identified, providing a roadmap for continuing investigation in this promising field of study. Upon meticulous examination of the influence of RHA across diverse geotechnical domains, it has been discerned that integration of approximately 4–12% of RHA substantially augments the short-term and long-term engineering attributes of the soil. Through this comprehensive review, the paper contributes to the ongoing exploration of innovative, sustainable, and effective techniques for soil stabilization.