Expansive soils undergo uncontrolled volumetric changes due to variations in moisture content. Consequently, the overlying structures, including pavements, are severely damaged. The common practice is to remove the natural expansive soil and replace it with a non-expansive soil. However, other economic solutions should be considered such as using stabilizers. In this paper, the effect of adding two stabilizers on the performance of an expansive soil is investigated. The hydrated lime is used as a chemical stabilizer and dolomitic limestone by-product (DLP) is used as a mechanical stabilizer. The study examines the effect of these stabilizers on the physical and mechanical properties of the soil mixtures. A series of tests are performed on expansive artificial soil-mixtures with lime contents of 3%, 6%, and 9% and DLP contents of 12%, 24%, and 48%. The tests include sieve analysis, Atterberg limits, modified Proctor, free swell, CBR, pH, and chemical analysis. The volume changes upon wetting are evaluated using free swell index (FSI) and swelling potential (SL), whilst, the effect of stabilizers on soil strength is assessed based on CBR value.