Mineralogical and Geotechnical Properties of Clayey Vertisols from Northern Cameroon: To Provide a Scientific Basis for Future Stabilization and Engineering Applications

This study presents an integrated geotechnical, mineralogical and geochemical characterization of clayey Vertisols developed under Sudano-Sahelian climatic conditions in northern Cameroon, with the aim to provide a scientific basis for future stabilization and engineering applications. Representative Vertisol samples were collected from the North and Far North regions and investigated using standard geotechnical tests, chemical analyses, and mineralogical identification by X-ray diffraction. The results reveal clay-rich materials dominated by fine fractions, with textures ranging from sandy clay to sandy heavy clay, and displaying low to high plasticity indices, reflecting strong smectitic influence. Geochemically, the Vertisols are characterized by high SiO₂ and Al₂O₃ contents, moderate to high Fe₂O₃ levels, elevated CIA values (57–83%), and significant cation exchange capacities, indicating advanced chemical weathering under seasonally contrasted tropical conditions. Mineralogical assemblages are composed by smectite, kaolinite, illite, quartz and K-feldspars, confirming both pedogenetic clay formation and inheritance from parent materials. These combined characteristics explain the pronounced shrink–swell behavior and vertic features observed in the field. Overall, the studied Vertisols exhibit physicochemical properties that make them promising raw materials for sustainable construction applications and environmental uses, if appropriate stabilization strategies are implemented to mitigate their expansive behavior.