Numerical investigation of setup effects in the vertical holding capacity of finless torpedo anchors

Abstract

This article presents a numerical-based study on the vertical holding capacity of a typical finless torpedo anchor embedded in a pure cohesive isotropic sol considering setup effects. A strategy based on two axisymmetric nonlinear finite elements (FE) models is proposed. In these models, the soil is represented with continuous solid elements with both plane translational and pore pressure degrees of freedom, which allow the modeling of the soil's strength regain after the installation of the anchor, i. e., the soil setup. The anchor is also modeled with solid elements, and its interaction with the soil is addressed with contact elements. Several analyses are conducted to evaluate setup effects, and, additionally, a parametric study on different soil undrained shear strengths and permeability coefficients is performed. The results obtained show that the permeability of the soil and its undrained shear strength have an important role in the setup process, and an inverse relationship between consolidation time and the permeability coefficient of the soil is observed. Finally, an analytical approach is calibrated with a reasonable agreement to the numerical results