Laboratory Investigation of Local Bending in Profiled Thermoplastic Pipes

Abstract

Full-scale pipe tests were conducted to investigate local bending on profiles of different thermoplastic pipes. Five profiled pipes including two lined corrugated, one box and one tubular profile of HDPE material and one ribbed profile of PVC material were considered. The study demonstrates that a three-dimensional bending mechanism governs the strains on some components of the pipe profiles. The local bending was particularly significant in the lined corrugated and the tubular profiled pipes. The mechanism of the local bending at the crown and the springline was different for lined corrugated pipes under biaxial loading. Ratios of the circumferential strains on the liner to those at the inner wall were higher at the crown/invert than the ratios at the springline. The liner with longer span was found to undergo even lesser strain relative to the liner with shorter span. The local bending did not affect the strain on the other elements of the lined corrugated profile.