Numerical Investigation of Ship Anchor Penetration in Cohesive Baltic Sea Soil

Abstract

One of the main reasons for damage to embedded offshore infrastructure is anchor penetration. Sea cables, for example, are harmed either by direct anchor contact or by additional pressure caused by anchor dragging above the cable. A sufficient permanent burial depth is required to minimize the risk of failure due to anchor penetration. This work presents the numerical simulation of the penetration process of two ship anchors (HHP AC-14 and Spek) in cohesive soil of the Baltic Sea. The simulations are carried out using the Coupled Euler-Lagrange (CEL) method in Abaqus/Explicit. Baltic Sea silt, under undrained conditions, is modeled. For the creep, relaxation behavior, and velocity dependence of the soil, the visco-hypoplastic constitutive model, according to [1], is used. Soil parameters have been obtained by laboratory tests. A parametric study is conducted varying anchor type, mass, and velocity, which significantly influence penetration depth and penetration behavior.