Ultimate Bearing Characteristics Analysis of a Novel Anchor Structure for Floating Offshore Wind Turbine under Mooring Line Failure Conditions

Abstract

This paper introduces a novel three-anchor combined suction anchor (TACSA) structure and evaluates the ultimate bearing characteristics of two mooring types under mooring line failure scenarios: single-primary-anchor mooring (SPAM) and dual-primary-anchor mooring (DPAM). Utilizing the finite element software ABAQUS, the ultimate bearing capacity and failure mode of the anchor were analyzed under the mooring line failure conditions. The findings indicate that with an increase in the deflection angle, the bearing capacity of the anchor experiences a gradual decline. A comparison of the two types of mooring revealed that DPAM resulted in a reduced descending speed of the bearing capacity and a smaller deflection angle of the anchor compared to the SPAM. In the SPAM system, the occurrence of linear plastic damage is contingent upon the attainment of a deflection angle of 45°. In the DPAM system, such damage manifests when the deflection angle exceeds 60°. These findings suggest that the synergistic effect between the anchors and the soil is enhanced in the DPAM system. Consequently, DPAM system demonstrates superior ultimate bearing characteristics and a reduced rotation degree, rendering it more effective in resisting the torque load induced by the deflection angle compared to SPAM system.

Keywords

Offshore wind power / Bearing capacity / Failure modes / Three-anchor combined suction anchor / Mooring types

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Harbin Engineering University and Springer-Verlag GmbH Germany, part of Springer Nature

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