Differential Equation for Evaluating Transverse Buckling Behavior of Tensile Armour Wires

The present paper addresses aspects related to transverse tensile armour buckling in flexible pipes. An analytical model for evaluating the tensile armour buckling capacity is presented based on formulating the linearised differential equation describing the transverse stability of the thin curved wire assuming no friction. This is followed by a numerical study based on FE analysis to evaluate the extra capacity from friction during cyclic bending behaviour and where the yield stress is used as the failure criteria. The results is then compared to test data and a design criteria for transverse tensile armour buckling proposed.