In-service life estimation of damaged gas pipelines: Full-scale experiments and finite element analyses

Statistical analysis reveals that mechanical damage is the first cause of incidents on gas transmission pipelines. They can be created by third party activities such as excavator tooth impact or by interaction between the pipe and rocks. To manage the damaged pipeline safely without useless cost, there is a need to investigate the mechanical behaviour of dented pipelines under a varying internal pressure. The purpose of this study is to characterize the stress and strain field around defects in pipes submitted to cyclic pressure loadings in order to estimate their residual lifetime. Full 3D finite element analyses of the denting process followed by cyclic loading are performed. Full-scale experiments on dented sections are planned.