NUMERICAL ANALYSIS OF ULTIMATE BEARING CAPACITY OF UNDRAINED TWO-LAYERED CLAYS

The ultimate bearing capacity of a rigid strip footings resting on undrained two-layered clays Is estimated using an elastio-plastic finite element method. For a wide range of problem geometries, the results are obtained and presented with the terms of modified bearing capacity factor. The results are compared with those obtained from existing limit analysis, empirical and semi-empirical solutions, upper bound solutions, as well asfinite element analysis based on the upper and lower bound limit theorems. The comparisons show that the elasto-plastic displacement finite element method can give robust and accurate solutions to the true limit bearing capacity of clay profiles. And the solutions of the paper have a good agreement with the lower bound solutions. However the upper bound solutions can overestimate the bearing capacity of undrained two-layered clays in some instance. The classical empirical solutions can underestimate the collapse load.