Out-of-plane bending stiffness and hotspot stress based on advanced numerical analysis techniques. (3rd October 2019)

• Record Type: Journal Article
• Authors: Choung, Joonmo; Lee, Jae-bin
• Is Part Of: Ships and offshore structures. Volume 14(2019)Supplement 1
• Page Start: 148
• Page End: 160
• Publication Date: 2019-10-03
• Subjects: OPB moment -- interlink angle -- tension angle -- hotspot stress -- three-link analysis -- multi-link analysis -- stress interpolation; Ships -- Periodicals; Offshore structures -- Periodicals; Marine engineering -- Periodicals; Marine engineering -- Technological innovations -- Periodicals; Ocean engineering -- Periodicals; Ocean engineering -- Technological innovations -- Periodicals; 623.8
• DOI: 10.1080/17445302.2018.1561174
• Languages: English
• ISSNs: 1744-5302

Abstract

ABSTRACT: This paper aims to presents an integrated procedure to reach the out-of-plane bending (OPB) moment-induced hotspot stress distribution for the mooring chains of an 8MW class floating offshore wind turbine platform (FOWT). Three-link models of the mooring chains were used to obtain the OPB stiffness, mid-span stress distribution, hotspot stress, and stress concentration factor based on the prescribed rotation approach (PRA), direct tension approach (DTA), and empirical formula. Multi-link analyses were also conducted to build a tension angle-interlink angle relationship between two successive links at a given tension level. A combination of three-link and multi-link analyses produced the relation of the hotspot stress-tension angle. After a stress interpolation procedure for the hotspot stress history, the hotspot stress range distributions were presented using rainflow counting technique. The tension-induced stress range distribution well followed the Rayleigh distribution, while the OPB moment elevated the hotspot stress which will seriously affect the fatigue accumulation.