In recent years anisotropic pipe material properties have gained more interest due to offshore; strain based design and fracture arrest topics.
The effect of anisotropic UOE pipe material characteristic is analyzed in this contribution. Both, anisotropic strain dependent values (Lankford) and anisotropic strength dependent factors (Hill) are compared, and their impact on load bearing and plastic strain capacity is investigated.
Several common load cases as internal and external pressure as well as bending are investigated. An analysis of the structural behavior concerning burst pressure and transverse strain capacity, collapse pressure, maximum bending moment and critical buckling strain is performed depending on yield strength variation. Therefore the above load and strain capacities are investigated based on present material anisotropy as well as numerical parametric studies.
For the internal pressure as dominating load case, it was found that a higher yield strength in the longitudinal direction decreases burst pressure and increases transverse strain capacity. An increase of radial yield strength increases burst pressure as well as transverse strain capacity.
For collapse applications, higher radial and transverse yield strength is beneficial as well as a lower longitudinal yield strength.
Increasing longitudinal and radial yield strength leads to beneficial structural responses in terms of bending. Increase of transversal yield strength is thus not recommended as the maximum bending moment is not affected and critical buckling strain is decreased.
Further it becomes clear from the above various parametric studies that the structural behavior is prone to differ for every set of distinct anisotropic parameters and the load cases. On the other hand selection of distinct anisotropic material can promote the desired structural behavior.