Análise numérica da capacidade de carga de âncoras torpedo considerando efeitos de setup

Abstract

The aim of this work is to develop a methodology of analysis and design of torpedo anchors for floating structures mooring systems considering setup effects. Soil disturbance caused by the anchor installation induces an excess of pore pressure generation around the anchor, leading to a loss on its holding capacity. As the excess pore pressure dissipates over time, though, the anchor’s holding capacity is observed to be recovered. This process is known as setup. The methodology is based on the finite element method by using axisymmetric isoparametric solid elements for soil and anchor representation. The soil-anchor interface is simulated by using surface-to-surface contact discretization with penalty type contact properties. Initial soil stress state is modeled by the cylindrical Cavity Expansion Method. Over the parametric study performed it was stated that soil permeability and undrained shear strength plays important role in setup process. Additionally, the results obtained were compared to some analytical methodologies for prediction of holding capacity to verify the proposed method with reasonable agreement.