Geotechnical Mapping of Clayey Subgrade Soils Characteristics: A Case Study from Tebessa City (Algeria)

Mapping of soils is essential when quantifying the relation between soils parameters and risk of swelling subgrades. Numerical mapping of soils areas affected by expansive clay minerals is essential when designing the pavements structures. In this paper, a simple method for automatic mapping of expansive clayey soils was proposed. 40 samples from subgrades of Tebessa city were subjected to various laboratory tests. The different geotechnical data were mapped to classify the subgrade soils and hazard delimitation of swelling areas using the geo-statistical method and automatic mapping technology. The results showed that soils were clayey marl. The Montmorillonite are observed abundant with small proportion of illite and kaolinite. These maps could be used to draw up the strategies of the clayey subgrade soils improvement and roads’ design. Also the new soils mapping method has the advantages of being quick, objective and helpful to the engineers to localize the hazard zone in the study area.