Buckling Analysis of Plastic Pipe Reinforced by Cross-Winding Steel Wire Under Bending

A plastic pipe reinforced by cross helically wound steel wires (PSP) has been developed rapidly in China as a new type of metal-plastics composite pipes. To deeply understand the mechanical properties of PSPs under pure bending, a four-layer analytical model is proposed based on Donnel theory. Additionally, a 3D finite element model (FEM) of PSPs under bending using an eigenvalue method is present. Good agreement between the theoretical results and finite element results is obtained, which shows that the proposed FEM can predict the buckling moments of PSPs. Further, A FEM of the PSP under bending is preformed by using the geometrically nonlinear finite element analysis (FEA). The buckling load is found by searching a bifurcation point on the geometrically nonlinear deformation path and the corresponding buckling mode is obtained from the eigenvalue analysis. Finally, the influence of the pipe lengths, design parameters and initial flaws on the buckling moment is analyzed using nonlinear FEA.