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Evaluation of Shape Parameter Effect on the J-R Curve of Curved CT Specimen Using Limit Load Method

한계하중법을 이용한 Curved CT 시험편의 파괴저항곡선에 미치는 형상변수 영향 평가

  • Shin, In Hwan (Central Research Institute, Korea Hydro Nuclear Power Corporation) ;
  • Park, Chi Yong (Central Research Institute, Korea Hydro Nuclear Power Corporation) ;
  • Seok, Chang Sung (Dept. of Mechanical Engineering, SungKyunKwan Univ.) ;
  • Koo, Jae Mean (Dept. of Mechanical Engineering, SungKyunKwan Univ.)
  • 신인환 (한국수력원자력(주) 중앙연구원) ;
  • 박치용 (한국수력원자력(주) 중앙연구원) ;
  • 석창성 (성균관대학교 기계공학과) ;
  • 구재민 (성균관대학교 기계공학과)
  • Received : 2014.03.14
  • Accepted : 2014.05.02
  • Published : 2014.07.01

Abstract

In this study, the effect of shape parameters on the J-R curves of curved CT specimens was evaluated using the limit load method. Fracture toughness tests considering the shape factors L/W and $R_m/t$ of the specimens were also performed. Thereafter, the J-R curves of the curved CT specimens were compared using the J-integral equation proposed in the ASTM (American Society for Testing and Materials) and limit load solution. The J-R curves of the curved CT specimens were also compared with those of the CWP (curved wide plate), which is regarded to be similar to real pipe and standard specimens. Finally, the effectiveness of the J-R curve of each curved CT specimen was evaluated. The results of this study can be used for assessing the applicability of curved CT specimens in the accurate evaluation of the fracture toughness of real pipes.

Keywords

Curved CT Specimen;J-R Curve;Fracture Toughness;Limit Load Method;Plastic ${\eta}$-Factor

Acknowledgement

Supported by : National Research Foundation of Korea (NRF)

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