Laboratory Assessment of the Effectiveness of Rice Husk Ash, Rice Husk, and Groundnut Shells in Soil Improvement

Utilizing waste materials to improve soil properties can reduce construction costs, benefiting the environment. To this end, studies are conducted to examine the potential for using agricultural wastes, such as rice husk (RH), groundnut shells (GS), and rice husk ash (RHA), to modify clayey sands from Mysore district, India. This paper focuses on the results of Atterberg limits, compaction, unconfined compressive strength (UCS), and California bearing ratio (CBR) tests conducted on mixtures of soil-RHA-RH + GS. This study investigates the effects of varying weight percentages of RHA (5, 10, 15, and 20%) and RH and GS (1, 2, 3, 4, and 5%) on the strength of soil-RHA-RH + GS mixtures, at curing periods of 1, 7, 14, and 21 days. The results indicated a decrease in the maximum dry density (MDD) and an increase in the optimum moisture content (OMC). Additionally, Atterberg limits, CBR, and UCS showed slight improvement with the addition of RHA, RH, and GS. The soil mixture was examined using scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDS).