Influence of Soil Destructuration on Bearing Capacity Estimation of Square Footings in Structured Clay

The existence of a metastable skeletal structure in natural deposits of structured clays influences soil to behave in a significantly different manner than that expected from a reconstituted specimen prepared in the laboratory. Degradation of soil structure with continuous plastic deformation is identified as the key reason behind such behavioural disparity. This research emphasizes the need to consider in situ soil structure, its degradation under loading, and the consequent evolution of stress-induced anisotropy in bearing capacity analysis of square footings in structured clay. The bearing capacity factor for a square footing in structured clays demonstrates a substantial decrease due to the soil destructuration process. The effect of the footing-soil interface condition on footing bearing capacity is also studied. Moreover, results from a field load test conducted on a square footing in structured clay in Brazil are predicted through finite element analyses. Numerical prediction is in very good agreement with reported field data.