Dynamic installation of OMNI-Max anchors in clay: numerical analysis

This paper reports the results from three-dimensional dynamic finite-element analysis undertaken to provide insight into the behaviour of OMNI-Max™ anchors during dynamic installation in non-homogeneous clay. The large-deformation finite-element analyses were carried out using the coupled Eulerian–Lagrangian approach, modifying the simple elastic–perfectly plastic Tresca soil model to allow strain softening, and incorporate strain-rate dependency of the shear strength using the Herschel–Bulkley model. The results were validated against field data prior to undertaking a detailed parametric study, exploring the relevant range of parameters in terms of anchor mass, impact velocity and soil strength. To predict the embedment depth in the field, an improved rational analytical embedment model, based on the total energy method, was proposed, with the large-deformation finite-element data used to calibrate the model.