Local approach to fracture applied to the analysis of a full size test on a pipe containing a girth weld defect

Clement Soret (1) , Yazid Madi (1, 2) , Vincent Gaffard (3) , Jacques Besson (1)

1 CDM - Centre des Matériaux
2 Ermess EPF
3 TOTAL S.A.

A welded pipeline segment containing a girth weld defect is tested under combined internal pressure and bending. The test is then analyzed with respect to both overall elasto-plastic behavior and crack propagation up to failure. The analysis is carried out using the finite element method. Constitutive equations for the plastic behavior of both weld metal and base metal are determined using tests carried out on smooth and notched bars. The cracking behavior of the weld metal is characterized using SENT specimens. The detailed analysis of the test allows to better understand boundary conditions and to represent the pipe overall behavior. The GTN model is used to represent damage growth up to failure in the weld metal. The simulation then allows representing the pipe behavior up to failure due to through thickness crack propagation.

Mots clés: Girth weld; Full size test; Crack propagation; GTN model

Domaines: Science des matériaux [cond-mat.mtrl-sci]

Clement Soret, Yazid Madi, Vincent Gaffard, Jacques Besson. Local approach to fracture applied to the analysis of a full size test on a pipe containing a girth weld defect. Engineering Failure Analysis, 2017, 82, pp.404-419. ⟨10.1016/j.engfailanal.2017.07.035⟩. ⟨hal-01634056⟩