Numerical Simulation of a Building Collapse on Sandy Clay of Douala City in Cameroon

Since land-use losses are very costly for the community, it is important to consider appropriate construction solutions. In the particular case of the city of Douala, we want to understand the mechanisms of triggering a progressive collapse of infrastructural origin. A global numerical approach has been used. It was based on hypotheses concerning the modification of the initial framework by taking off a vertical carrier, the imposition of a displacement and the observation of the deformations as a function of time. The numerical simulation from the Cast3M code allowed to analyze the behavior of the soil-structure interface and its influence on the superstructure. As a result, the high compressive forces at the point of application of the displacement cause a failure due to the settlement of the soil within the zone influenced by the stress bubble, hence the need to adapt the geometry of foundations to geotechnical context. The study revealed a breaking stress of 0.1Mpa. The deformation diagrams show that ruin occurs following a localized rupture of the soil, the appearance and then the propagation of cracks on the framework, before the collapse by domino effect of the whole.