Interlocked armor layers of unbonded flexible risers may crush when risers are being launched. In order to predict the behavior of interlocked armor layers, they are usually simplified as rings with geometric and contact nonlinearity ignored in the open-literature. However, the equivalent thickness of the interlocked armor layer has not been addressed yet. In the present paper, a geometric coefficient γ is introduced to the equivalent stiffness method, and a linear relationship between γ and geometric parameters of interlocked armor layers is validated by analytical and finite element models. Radial stiffness and equivalent thickness of interlocked armor layers are compared with experiments and different equivalent methods, which show that the present method has a higher accuracy. Furthermore, hoop stress distribution of interlocked armor layer under crushing is predicted, which indicates the interlocked armor layer can be divided into two compression and two expansion zones by four symmetrically distributed singular points. Keywords: Flexible riser, Carcass layer, Pressure armor layer, Crushing


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    Title :

    Crushing study for interlocked armor layers of unbonded flexible risers with a modified equivalent stiffness method


    Contributors:
    Shaofei Ren (author) / Wencheng Liu (author) / Ying Song (author) / Hang Geng (author) / Fangguang Wu (author)


    Publication date :

    2019




    Type of media :

    Article (Journal)


    Type of material :

    Electronic Resource


    Language :

    Unknown




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