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Numerical Analysis of Local Joint Flexibility of K-joints with External Plates Under Axial Loads in Offshore Tubular Structures

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Abstract

The Local Joint Flexibility (LJF) of steel K-joints reinforced with external plates under axial loads is investigated in this paper. For this aim, firstly, a finite element (FE) model was produced and verified with the results of several experimental tests. In the next step, a set of 150 FE models was generated to assess the effect of the brace angle (θ), the stiffener plate size (η and λ), and the joint geometry (γ, τ, ξ and β) on the LJF factor (fLJF). The results showed that using the external plates can decrease 81% of the fLJF. Moreover, the reinforcing effect of the reinforcing plate on the fLJF is more remarkable in the joints with smaller β. Also, the effect of the γ on the fLJF ratio can be ignored. Despite the important effect of the fLJF on the behavior of tubular joints, there is not available any study or equation on the fLJF in any reinforced K-joints under axial load. Consequently, using the present FE results, a design parametric equation is proposed. The equation can reasonably predict the fLJF in the reinforced K-joints under axial load.

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Authors and Affiliations

  1. Department of Civil Engineering, Faculty of Engineering, University of Guilan, Guilan, Iran

    Hossein Nassiraei & Amin Yara

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  1. Hossein Nassiraei
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  2. Amin Yara
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Correspondence to Hossein Nassiraei.

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Article Highlights

• 150 FE models were produced to evaluate the LJF in CHS K-joints with plates under axial load;

• The effect of the θ, β, γ, ξ, and τ, λ, and η is evaluated;

• A design formula is proposed to determine the fLJF.

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Nassiraei, H., Yara, A. Numerical Analysis of Local Joint Flexibility of K-joints with External Plates Under Axial Loads in Offshore Tubular Structures. J. Marine. Sci. Appl. 21, 134–144 (2022). https://doi.org/10.1007/s11804-022-00302-w

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  • DOI: https://doi.org/10.1007/s11804-022-00302-w

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