Numerical modelling of anchor foundation in dense sand

Anchors and anchoring systems are widely used in different structures with different embedment, size, and shapes. The Finite Element Method has the ability to handle complex soil stratigraphy and it also has the potentiality of solving different soil-structure interaction problems. Presently evolved, almost all of the prevailing sophisticated models are very complex and incomplete in the sense that they do not define important factors such as strain localization, strain softening, etc. Above important factor overlooked in most of the current geotechnical models is a strong link between the model and a reliable set of experimental data. Mohr-Coulomb failure surface has corners or singularities, and therefore it is not mathematically convenient to use particularly for 3D problems because of discontinuties of gradient occur at edges and tip of the hexagonal shape yield surface pyramid. In this study, different approximation models are used to determine the appropriate models with respect to experiment. Furthermore, parametric studies are done on peak frictional and dilatancy angles. This study validated the rigorous 3D FE models, incorporating simple strain softening law for anchor foundation in dense sand using in-house finite element program. DP compromise cone predictions are found to be in better agreement with the experimental results. Dilatancy of sand makes significant effect on the uplift behavior of anchors. The greater dilation angle is resulted from the higher collapse load and displacement. With the increase of friction angle and embedment ratio, the effecet of dilatancy is more remarkable.