Ultimate fracture capacity of pressurised pipes with defects – Comparisons of large scale testing and numerical simulations

• Published in: Engineering fracture mechanics Vol. 75; no. 8; pp. 2352 - 2366
• Main Authors: Berg, E., Østby, E., Thaulow, C., Skallerud, B.
• Format: Journal Article
• Language: English
• Published: Tarrytown, NY Elsevier Ltd 01.05.2008; Oxford Elsevier
• Subjects: Biaxial loading; Ductile crack growth; Exact sciences and technology; Fracture mechanics; Fracture mechanics (crack, fatigue, damage...); Fundamental areas of phenomenology (including applications); Inelasticity (thermoplasticity, viscoplasticity...); Large scale testing; Line-spring; Physics; Solid mechanics; Structural and continuum mechanics; Ductile crack growth; Biaxial loading; Fracture mechanics; Large scale testing; Line-spring; Large pipe; Biaxial strain; Rupture; Underwater pipeline; Biaxial load; Wall thickness; Experimental study; Modeling; Crack propagation; Yield strength; Ductile material; Bending test
• ISSN: 0013-7944; 1873-7315
• DOI: 10.1016/j.engfracmech.2007.09.004

In this paper results from large scale 4-point bending tests of pipe-segments are compared with numerical analyses using LINK pipe. The experiments were carried out as a part of the joint industry project Fracture Control – Offshore Pipelines. The comparisons between large scale testing of pipelines and numerical analyses also address the effect of biaxial loading on the strain capacity. The defect is positioned on the tension side of the pipe when applying the load. A parametric study on changing the nominal wall thickness of the pipe is carried out. Due to variation in the yield stress, a parametric study to see the effect of this variation was also performed. The results demonstrate that ductile crack growth and biaxial loading are important elements in fracture assessment procedures for pipelines.