ENHANCEMENT OF THE ENGINEERING PROPERTIES OF SOIL USING CORNCOB ASH AS A SUSTAINING AGENT

Enhancement of soil properties can be achieved by modifying the existing characteristics of soil through the use of various enhancement agents.This modification may involve altering soil gradation by mixing it with geopolymers or biopolymers to improve the strength and durability of weak soils.Soil improvement methods generally include mechanical stabilization or the addition of chemical additives, which directly or indirectly modify soil behavior.The effectiveness of soil enhancement is primarily influenced by three key parameters: improvement in permeability, increase in strength and durability to enhance load-bearing capacity, and improved resistance of soil against natural, anthropogenic, and environmental factors.Based on extensive literature review and experimental investigations, it was observed that an increase in Corncob Ash (CCA) content leads to a reduction in both liquid limit and plastic limit of the soil.The shrinkage limit initially increases with increasing CCA content and subsequently decreases beyond a certain percentage.For virgin soil, the Optimum Moisture Content (OMC) and Maximum Dry Density (MDD) were found to be 0.161 and 1.96 g/cc, respectively.When the soil was treated with 0.7% CCA, the OMC and MDD values reduced to 0.144 and increased slightly to 1.97 g/cc.At 1.4% CCA content, the OMC further decreased to 0.135, while the MDD increased to 1.99 g/cc.With 2.1% CCA, the OMC reduced to 0.124 and the MDD increased to 2.015 g/cc.For 2.8% CCA content, the OMC reached 0.121, and the MDD increased significantly to 2.216 g/cc.The maximum Unconfined Compressive Strength (UCS) of 2.413 was achieved at a CCA content of 2.1%.Therefore, the optimum Corncob Ash content for soil stabilization was determined to be 2.1%, beyond which no significant improvement in strength was observed.