Plastic Collapse Analysis of Pipe Bends Under Out-of-Plane Moment and Internal Pressure Loading

Abstract

Two recently proposed Design by Analysis criteria of plastic collapse based on plastic work concepts, the Plastic Work criterion and the Plastic Work Curvature criterion, are applied to a strain hardening pipe bend arrangement subject to combined pressure and out-of-plane plane moment loading. Calculated plastic pressure-moment interaction surfaces are compared with limit surfaces, large deformation analysis instability surfaces and plastic load surfaces given by the ASME Twice Elastic Slope criterion. The results show that both large deformation theory and material strain hardening have a significant effect on the elastic-plastic response and calculated static strength of the component.