LAUSR

The existence of expansive subgrades is a challenge especially during pavement construction due to its drastic volume changes. In this case, the common practice is to remove the natural expansive soil and replace it with non-expansive soil. However, this solution becomes unviable for deep long extending formations of natural expansive soils. Therefore, efforts have been done in order to improve the properties of expansive soil using different types of stabilizers. In this paper, two types of stabilizing agents are investigated: hydrated lime and dolomitic limestone by-product. A testing program is selected to evaluate the swell-strength behaviour of artificially prepared sand-expansive clay mixtures. The testing program includes Atterberg limits, modified Proctor, free swell, CBR, pH and chemical analysis tests. Moreover, the soil expansivity and strength after treatment are evaluated based on relationships proposed by literature and the Egyptian Code.