Crack-tip constraints of through-wall cracked pipes and its similarity to curved wide plates

• Published in: Journal of mechanical science and technology Vol. 30; no. 10; pp. 4407 - 4411
• Main Authors: Jang, Youn-Young, Jeong, Jae-Uk, Huh, Nam-Su, Kim, Ki-Seok, Cho, Woo-Yeon
• Format: Journal Article
• Language: English
• Published: Seoul Korean Society of Mechanical Engineers 01-10-2016; Springer Nature B.V; 대한기계학회
• Subjects: Control; Dynamical Systems; Engineering; Finite element method; Fracture mechanics; Fracture toughness; Industrial and Production Engineering; Mathematical analysis; Mechanical Engineering; Pipe; Plastic deformation; Plastic strain; Plates; Similarity; Solvents; Strain hardening; Stresses; Vibration; 기계공학; Curved wide plate; stress; Through-wall cracked pipe; Crack-tip constraint; Finite element analysis; Stress triaxiality
• ISSN: 1738-494X; 1976-3824
• DOI: 10.1007/s12206-016-0902-2

In the present study, the effects of pipe geometries, material properties and loading conditions on crack-tip constraints of pipes with circumferential Through-wall crack (TWC) were investigated via systematic 3-dimensional (3-D) Finite element (FE) analyses. The crack-tip constraints were quantified by
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-stress, and to characterize the elastic-plastic strain hardening material behavior, Ramberg-Osgood (R-O) material was employed. Based on the FE results, it was observed that crack-tip constraints of pipes with TWC were dependent on crack length and thickness of pipe, however, the effects of each variables decreased as either thickness of pipe becomes thinner or crack length becomes longer. Moreover, the effects loading modes on
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-stresses for thin-walled pipes with TWC are negligible. Finally, the present
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-stresses of pipes were compared with those of Curved wide plate (CWP) in tension to address the similarity of crack-tip constraints between pipe and CWP, which could be used to produce the CWP to measure the fracture toughness of pipes accurately.