Numerical Analysis for Estimating Penetration Depth by Ship-dragged Fluke Anchor

Abstract

Anchor penetration by ship anchoring is emerging as a major risk factor for submarine cable. A numerical analysis method was established to predict the anchor penetration depth by ship-dragged fluke anchor in relation to setting the optimal burial depth of submarine cable. The soil resisting forces (bearing force, friction force) generated during the anchor penetration process were calculated for each of the fluke, shank and mooring chain of the anchor. The results of the numerical analysis were compared with the existing chart values of Vryhof (2015). It was found that it is desirable to use the force coefficients of strip foundation for the fluke and shank, and the force coefficients of a single vertical pile for mooring chain. The numerical analysis well reproduced the penetration trajectory in which the inclination angle of the lower surface of fluke gradually converged to zero.