Evaluation of Monotonic Ultimate Pull-out Capacity of Plate Anchors in Sand

Plate anchors are increasingly used in the mooring of offshore floating structures for the recovery and generation of oil, gas and electricity. In this study, Finite Element analyses have been conducted to estimate the ultimate monotonic holding capacity of plate anchors embedded in dense sand subjected to inclined axial pull-out. In the analyses, an advanced constitutive model, the Hardening Soil Model with Small-Strain Stiffness, has been used to simulate the nonlinear behaviour of soil. A set of parametric studies has been conducted to investigate the effect of inclination angle and embedment ratio on the monotonic pull-out behaviour of plate anchors. Analogous Limit State Analysis (LimitState: GEO) modelling has also been carried out to validate the finite element results in terms of ultimate capacity. In addition, the results have been compared with well-established theoretical analyses as available in the literature. Generally, a good agreement has been obtained and some observations have been made on the pull-out behaviour of plate anchors, verifying that the FE analyses can be used to investigate the behaviour of plate anchors up to and including pull-out.