Viscoplastic Finite Element Analysis of Complex Geotechnical Problems

The principles of elasto/viscoplastic finite element analysis were presented and explained, and the results and the analysis of some geotechnical problems were presented in this work. Plasticity models such as von-Mises, Tresca, Drucker-Prager and Mohr-Coulomb models with associated and non-associated flow rules were incorporated in the viscoplastic algorithm. The ultimate bearing capacity of a rigid surface footing on weightless clayey soil, Tresca material, predicted by the elasto/viscoplasticity approach agrees very well with that obtained by Prandtl exact solution (only 1% above Prandtl exact solution). Solution was also presented for complex problems with no available solution such as the problem of an anchor buried in sands (Mohr-Coulomb materials), where large zones within the soil domain are dominated by tensile stresses as well as sharp changes in shear stresses.