End Bearing Capacity Factor for Annular Foundations Embedded in Clay Considering the Effect of the Adhesion Factor

摘要

New limit analysis solutions for the end bearing capacity of annular foundations in clay with linearly increasing shear strength are presented in the paper. The strength profile of clay corresponds to a typical case of a normally consolidated clay in deep water, where the strength at the ground surface is defined as zero and increases linearly with the depth. The annular foundation has internal and external radii and is embedded in clay, where the adhesion factor representing the strength at the soil-structure interface is also taken into account. Using the lower and upper bound finite element limit analysis, the end bearing capacity factor of this problem can be obtained based on three considered dimensionless parameters, which are the ratio between the internal radius and the external radius, the embedded depth ratio, and the adhesion factor. The collapse mechanisms of annular foundations in clay are also examined and discussed in the paper to portray the effects of the radius ratio, the depth ratio, and the adhesion factor.