<p>In recent years, geotechnical engineers preferred environmentally friendly and sustainable techniques to improve the engineering characteristics of expansive soil. This paper focuses on the comparative study of the enhancement in engineering properties of expansive soil using lime and waste eggshell powder. A series of laboratory tests such as Unconfined Compressive Strength Test, pH test, Free swell Index Test, Swelling Pressure Test, California – Bearing Ratio test and Atterberg’s limit test were performed for evaluating the engineering behaviour of expansive soil with lime and waste eggshell both individually and together. The experimental test results showed that the combined admixtures significantly improve the engineering characteristics of the soil. The maximum value of compressive strength at the inclusion of 9% lime and 12% waste eggshell powder was observed to be 306 kPa. The swell pressure of the treated soil showed up to a reduction till 2.32 at the inclusion of 3% lime and 12% waste eggshell powder. In all the tests, the combined admixtures exhibited greater efficiency when compared to individual inclusion of lime and waste eggshell. Thus, the investigation results confirmed the efficient use of lime and waste eggshell powder at optimum percentages as soil-stabilizing material and made them suitable for field applications.</p>