Failure of X52 wrinkled pipeline subjected to monotonic bending deformation and internal pressure

This study was undertaken to investigate and understand the complete post-wrinkling behavior and failure modes of pressured X52-grade wrinkled buried energy pipeline when subjected to monotonically increasing bending deformation. This study involved both experimental and numerical investigations. Detailed parametric study was undertaken using a numerical approach, and it was found that the X52-grade steel linepipe generally exhibits a ductile behavior. The parametric study shows that X52 linepipe with a diameter-to-thickness ratio of 35 or higher does not fail in rupture. However, these linepipes eventually fail in a deformation mode due to excessive cross-sectional deformation. It was also found that the rupture failure occurs only at the wrinkle face of the bent linepipe.