This paper presents the influence of lime addition on the geotechnical properties of an expansive Algerian clayey soil. The studied soil was classified as a fat clay (CH) with high plasticity according to the unified soil classification system (USCS). 2, 4 and 6% lime was added to the clay soil in order to studied their effect on the physical and mechanical properties of the studied soil. The pH variation, consistency limits, compaction, swell, unconfined compressive strength, mineralogical and microstructural analysis are particularly investigated. For the purpose of studying the effect of curing time on soil strength, treated specimens were cured for 1, 7 and 28 days. Tests results indicate that the pH of the studied soil was significantly increased after their treatment with lime, which indicates the beginning of chemical reactions between lime and clay soil. After lime treatment the studied soil become more friable and easier to work with a higher unconfined compressive strength (UCS) due to the flocculation of the soil structure and the production of new cementation products such as CSH and CAH

The operational dams in Algeria lose 32 million m3 of water storage capacity each year, and fifteen of these dams are threatened by siltation. This investigation forms a component of a management strategy for dredged silt in the Gargar Dam, the third-largest dam in Algeria with considerable sedimentation. This paper comprises two main axes: a detailed experimental study based on the studied dam mud's physico-chemical, rheological, and mechanical analysis. The second part is based on the study of the valorization of Gargar mud to be acceptable for use in road civil engineering. In order to obtain this goal, the Gargar mud was treated with lime (0-6%), sand (20%), and natural pozzolana (20%). Test results show that the properties of Gargar mud are significantly improved after treatment, and the soil becomes more friable and more resistant; it can therefore be used as a foundation layer in road civil engineering.