Abstract：A numerical model of 3D FEM for suction tapered bucket foundations is established based on the Mohr-Coulomb constitutive criterion, and is also verified by model tests. On this basis, the analysis and computation are carried out, and the dependency relationship between the factors of aspect ratio and bucket slop and the bearing capacity of tapered bucket foundation in saturated soft clay is studied. Based on the empirical expression by Vesic, a vertical bearing formula for tapered single bucket foundations, with the action that the bucket is cohered with the contacted clay, is presented. A comparison shows that the calculated results of this formula is consistent with those of FEM.
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