Fatigue Sensitivity Analysis of Steel Catenary Riser near Touchdown Point

doi:10.1007/s12204-017-1876-7

Journal of shanghai Jiaotong University (Science) ›› 2017, Vol. 22 ›› Issue (5): 570-576.doi: 10.1007/s12204-017-1876-7

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Fatigue Sensitivity Analysis of Steel Catenary Riser near Touchdown Point

WANG Kunpeng¹* (王坤鹏), JI Chunyan¹(嵇春艳), XUE Hongxiang² (薛鸿祥), TANG Wenyong² (唐文勇)

(1. School of Naval Architecture and Ocean Engineering, Jiangsu University of Science and Technology, Zhenjiang 212003, Jiangsu, China; 2. State Key Laboratory of Ocean Engineering, Shanghai Jiao Tong University, Shanghai 200240, China)
(1. School of Naval Architecture and Ocean Engineering, Jiangsu University of Science and Technology, Zhenjiang 212003, Jiangsu, China; 2. State Key Laboratory of Ocean Engineering, Shanghai Jiao Tong University, Shanghai 200240, China)

Online:2017-09-30 Published:2017-09-30
Contact: WANG Kunpeng (王坤鹏) E-mail: wangkunpeng@just.edu.cn

Abstract

Abstract: By transforming the platform response obtained from coupled hydrodynamic analysis to the top motions of steel catenary riser (SCR), the nonlinear dynamic analysis of the SCR is carried out in Abaqus/Aqua. In this analysis, the SCR-seabed interaction is well taken into account by introducing the seabed trench model and hysteretic seabed model. The fatigue damage of the SCR near touchdown point (TDP) is calculated using rain-flow counting methodology, and the sensitivity of the fatigue damage to the seabed and wave parameters are investigated. The results indicate that as seabed stiffness increases, the fatigue life and its sensitivity to seabed stiffness decrease. Seabed trenching may benefit the fatigue life of the SCR and the trench position should be elaborated for realistic fatigue damage prediction. Due to the induced platform response, significant wave height and spectral peak period have significant effects on the fatigue damage, thus the short-term sea state bins should be carefully selected from the wave scatter diagram.

Key words: touchdown point| fatigue sensitivity| seabed trench| hysteretic seabed model

摘要： By transforming the platform response obtained from coupled hydrodynamic analysis to the top motions of steel catenary riser (SCR), the nonlinear dynamic analysis of the SCR is carried out in Abaqus/Aqua. In this analysis, the SCR-seabed interaction is well taken into account by introducing the seabed trench model and hysteretic seabed model. The fatigue damage of the SCR near touchdown point (TDP) is calculated using rain-flow counting methodology, and the sensitivity of the fatigue damage to the seabed and wave parameters are investigated. The results indicate that as seabed stiffness increases, the fatigue life and its sensitivity to seabed stiffness decrease. Seabed trenching may benefit the fatigue life of the SCR and the trench position should be elaborated for realistic fatigue damage prediction. Due to the induced platform response, significant wave height and spectral peak period have significant effects on the fatigue damage, thus the short-term sea state bins should be carefully selected from the wave scatter diagram.

关键词: touchdown point| fatigue sensitivity| seabed trench| hysteretic seabed model

CLC Number:

P 752

WANG Kunpeng1* (王坤鹏), JI Chunyan1 (嵇春艳), XUE Hongxiang2 (薛鸿祥), TANG Wenyong2 (唐文勇). Fatigue Sensitivity Analysis of Steel Catenary Riser near Touchdown Point[J]. Journal of shanghai Jiaotong University (Science), 2017, 22(5): 570-576.

References 20

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Fatigue Sensitivity Analysis of Steel Catenary Riser near Touchdown Point

Fatigue Sensitivity Analysis of Steel Catenary Riser near Touchdown Point

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