Evaluation of Local Bending in Profile-Wall Polyethylene Pipes

Abstract

Thermoplastic pipes with a wide variety of wall geometries have been developed to obtain higher stiffness with utilization of less pipe material. The geometries of these profiles induce local bending, which may influence their structural performance. The localized deformations are investigated here for a range of commonly used pipe profiles using three-dimensional finite-element analysis. The study revealed that local bending governs the wall strains in some profiles. Among the three profile types considered, the effect of local bending was the greatest in the lined corrugated profiles. Circumferential strain distributions in the boxed and tubular profiles were almost uniform along the pipe axis, though axial and radial stress and strain indicated that these profiles also experienced local bending. While finite-element analysis using an axisymmetric idealization of the profiles appeared successful in capturing most of the characteristics of the three-dimensional profile response, certain aspects for the helically wound boxed profile were not captured well using this approach.