Correlation of fracture behavior between circumferentially cracked pipes and fracture specimens including ductile crack tearing

• Grant number: 13/01139-2
• Support Opportunities: Scholarships abroad - Research Internship - Post-doctor
• Effective date (Start): June 03, 2013
• Effective date (End): December 02, 2013
• Field of knowledge: Engineering - Naval and Oceanic Engineering - Marine and Ocean Structures
• Principal Investigator: Claudio Ruggieri
• Grantee: Diego Felipe Sarzosa Burgos
• Supervisor: Denys Rudi Michel
• Host Institution: Escola Politécnica (EP). Universidade de São Paulo (USP). São Paulo , SP, Brazil
• Research place: Ghent University (UGent), Belgium
• Associated to the scholarship: 12/00094-2 - Effects of Stress Triaxiality and J vs. CTOD relationship in SE(T) Specimens with Applications to Defect Assessment of Risers with Stationary and Propagation Cracks, BP.PD

Abstract

The offshore industry is moving to deeper waters to explore new oil and gas natural resources. It has motivated the development of efficient and innovative ocean systems; they have to meet severe design requirements, and some restrictions during installation and operation. Rigid risers are a key element to ensure a safe production. These risers are subjected to high levels of plastic deformation when they are installed by the reeling method. Unidentified flaws during the assembly process are subjected to large driving forces creating the appropriated condition for stable flaw propagation. As a result, the riser may become a potentially unsafe component. Currently, there are flaw assessment procedures applied to rigid risers that advocate the use of toughness values and fracture resistance curves geometrically dependent. Several studies have shown similar levels of constraint in the crack-tip between the SE(T) specimen and pipelines under tension/bending loads. However, the previous studies did not consider the stable crack propagation and, consequently, the change in the stress field ahead of the crack, which can modify the well known similarity between SE(T) and pipelines. This research aims to correlate the mechanical responses of nonstandard specimens, SE(T) and curved wide plate CWP, with pipelines/risers supporting large plastic deformations, considering the stable crack propagation. Numerical models using the computational cell approach are used to make predictions about the criticity of defects common to pipelines and risers; numerical models are calibrated using experimental results of specimens with low and high triaxiality. (AU)

Scientific publications

(4)

(References retrieved automatically from Web of Science and SciELO through information on FAPESP grants and their corresponding numbers as mentioned in the publications by the authors)

SARZOSA, DIEGO F. B.; SOUZA, RODOLFO F.; RUGGIERI, CLAUDIO. J-CTOD relations in clamped SE(T) fracture specimens including 3-D stationary and growth analysis. ENGINEERING FRACTURE MECHANICS, v. 147, p. 331-354, OCT 2015. (12/00094-2, 13/01139-2)

SARZOSA, DIEGO F. B.; RUGGIERI, CLAUDIO. A numerical investigation of constraint effects in circumferentially cracked pipes and fracture specimens including ductile tearing. INTERNATIONAL JOURNAL OF PRESSURE VESSELS AND PIPING, v. 120, p. 1-18, AUG-SEP 2014. (12/00094-2, 12/13053-2, 13/01139-2)

SARZOSA, DIEGO F. B.; VERSTRAETE, MATTHIAS; HERTELE, STIJN; DENYS, RUDI; RUGGIERI, CLAUDIO. Numerical simulation of ductile crack growth in medium wide plate specimens using 3-D computational cells. ENGINEERING FRACTURE MECHANICS, v. 168, n. A, p. 26-45, DEC 2016. (13/01139-2)

SARZOSA, DIEGO F. B.; VERSTRAETE, MATTHIAS; HERTELE, STIJN; DENYS, RUDI; RUGGIERI, CLAUDIO. Numerical simulation of ductile crack growth in medium wide plate specimens using 3-D computational cells. ENGINEERING FRACTURE MECHANICS, v. 168, p. 20-pg., 2016-12-01. (13/01139-2)