In recent years, Ashes of Agricultural Wastes (AAW) have emerged as promising Supplementary Cementitious Materials (SCMs) due to their high specific surface area, pozzolanic activity, and diverse morphologies. This paper aims to comprehensively review the potential use of AAWs in cement and concrete production and evaluate their influence on the fresh and hardened properties of concrete. Based on previous research, it was found that partial replacement of cement with 10-20% of rice husk ash (RHA) and sugarcane bagasse ash (SCBA), as well as 5-10% of cob ashes of corn (CAC) and peel ashes of cassava (PAC), generally results in reduced workability, with slump values often falling below 30 mm. This decrease is attributed to the porous nature of the ashes and the presence of unburned carbon particles. However, the same dosage ranges showed improvements in mechanical and durability characteristics. The normalized compressive strength was observed to be up to 1.2 times higher than that of control mixes, while water absorption and drying shrinkage were significantly reduced due to pore refinement. Life cycle assessment (LCA) data also demonstrated environmental advantages, particularly at 12.5% replacement of RHA and 5.5% SCBA, showing reduced carbon emissions and energy consumption. Among the various ashes studied, CAC and PAC received comparatively less attention in the literature despite being abundantly available and aligning with Sustainable Development Goals (SDGs). Therefore, this review also highlights the need for more targeted research on CAC and PAC, especially in paste and mortar applications, as well as detailed LCA studies.
Keywords: AAW; CAC; Cementitious systems; Concrete slump; Concrete strength; PAC; SCM.
© 2025. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.