The past decade has been characterized by the development of infrastructure in the main cities in Africa. This requires more comprehensive studies of geotechnical properties of the soil in the region with an aim of creating sustainable development.
To categorize the soil, the new approach has been adopted; using geological mapping to identify the soil’s characteristics by performing laboratory analysis. At present, the diagnosis of inherent capability is realized from soil samples taken on-site and then laboratory analysis is conducted.
The expansive soils greatly increase volume on contact with water and retract during dry up. This shrinkage and swelling properties of soil create a natural risk of differential movement of land when subject to the variations in water content. To educate builders about shrinkage risk, a hazard map showing through probabilistic determination of the risk of shrinkage and swelling was introduced in France. The infrastructure builds on expansive soils present enormous disorders, especially when no special provisions were made during their development. The particularities of expansive soils have long been known; there are multiple works and publications dedicated to expansive soils.
To remedy the deterioration of infrastructure on the clayey soil, the methods such as mechanical, chemical stabilization, of the soil have been used to restore the deterioration of the soil. All of the previous studies have focused on the use of lime, fly ash, cement, and fibers to improve the geotechnical properties of swelling clayey soils, whereas the application of chemical materials has been limited.
Landslide is a phenomena that is ascribed to the rotational or planar downward movement of rock or soil triggered by movements in the earth crust and in some cases, may involve the combination of different types of movements. Landslides are the cause of enormous material problems in most West African countries. As recent examples of the catastrophic public threats posed by these landslides, we can cite: the debris flow from the Iva valley in Nigeria, the landslide in the Bududa region, Uganda, in the Congo, and in western Cameroon with a combined human death of more than 4000. Landslides are not only destructive of lives and resources, they also degrade and destroy the resources essential to the well-being of humanity.
In some instances, with minimal internal deformation the displaced rubbles may coherently move along the disrupted surface. Whereas, in other cases, the displaced mass may move vertically downwards or may incline backwards towards the scarp.