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.
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
.
DOI: 10.1007/s12204-017-1876-7
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