Parametric Study and Formulation of Scfs in Axially Loaded Multi-Planar Tubular XT-Joints Reinforced with Internal Ring Stiffeners

نوع مقاله : مقاله کامل پژوهشی

نویسندگان

1 دانشگاه استرالیا

2 دانشکده مهندسی عمران، دانشگاه تبریز

10.22034/jcee.2021.42052.1968

چکیده

Many tubular joints commonly found in offshore jacket structures are multi-planar. Investigating the effect of loaded out-of-plane braces on the values of the stress concentration factor (SCF) in offshore tubular joints has been the objective of numerous research works. However, due to the diversity of joint types and loading conditions, several quite important cases still exist that have not been studied thoroughly. Among them are internally ring-stiffened multi-planar XT-joints subjected to axial loading. In the present research, data extracted from the stress analysis of 81 finite element (FE) models, verified using experimental test results, was used to study the effects of geometrical parameters on the chord-side SCFs in multi-planar tubular XT-joints reinforced with internal ring stiffeners subjected to two types of axial loading. Parametric FE study was followed by a set of the nonlinear regression analyses to develop four new SCF parametric equations for the fatigue analysis and design of axially loaded multi-planar XT-joints reinforced with internal ring stiffeners.

کلیدواژه‌ها

موضوعات


عنوان مقاله [English]

Parametric Study and Formulation of Scfs in Axially Loaded Multi-Planar Tubular XT-Joints Reinforced with Internal Ring Stiffeners

نویسندگان [English]

  • Hamid Ahmadi 1
  • Ahmad Kouhi 2
1 National Centre for Maritime Engineering and Hydrodynamics, University of Tasmania, TAS 7248, Australia and Centre for Future Materials, University of Southern Queensland, QLD 4350, Australia
2 Faculty of Civil Engineering, University of Tabriz , Iran
چکیده [English]

Many tubular joints commonly found in offshore jacket structures are multi-planar. Investigating the effect of loaded out-of-plane braces on the values of the stress concentration factor (SCF) in offshore tubular joints has been the objective of numerous research works. However, due to the diversity of joint types and loading conditions, several quite important cases still exist that have not been studied thoroughly. Among them are internally ring-stiffened multi-planar XT-joints subjected to axial loading. In the present research, data extracted from the stress analysis of 81 finite element (FE) models, verified using experimental test results, was used to study the effects of geometrical parameters on the chord-side SCFs in multi-planar tubular XT-joints reinforced with internal ring stiffeners subjected to two types of axial loading. Parametric FE study was followed by a set of the nonlinear regression analyses to develop four new SCF parametric equations for the fatigue analysis and design of axially loaded multi-planar XT-joints reinforced with internal ring stiffeners.

کلیدواژه‌ها [English]

  • Fatigue
  • Stress concentration factor (SCF)
  • Offshore jacket structure
  • Multi-planar tubular XT-joint
  • Internal ring stiffener

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