field and laboratory study of cantilever failure phenomenon in cohesive riverbanks

because it is not possible to recognize the mechanism of cantilever failure in field studies, this type of common failure in riverbanks is investigated in the laboratory. for this purpose, two samples of susceptible soil that forms an overhanging block in riverbanks are used for physical model tests to determine their physical, chemical and mechanical characteristics. soil blocks of different densities were formed and then undermined by hand at specific depths over specific time increments and the stability of the overhanging block were assessed at each step. the results showed that, under these laboratory study conditions, the dominant failure mechanism is toppling. this finding is in accordance with the overhanging failure pattern in the kordan riverbanks. it was also found that the failure mechanism in cohesive soil is progressive and accompanied by tension crack development. in loess material, the failure mechanism is momentary and no deformations in the upper part of the soil block are observed.