Transactions of the Korean Society of Mechanical Engineers A (대한기계학회논문집A)

The Korean Society of Mechanical Engineers (대한기계학회)
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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
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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.

본 연구에서는 한계하중법을 이용하여 Curved CT 시험편의 J-적분에 미치는 형상변수 영향을 평가하였다. 주요 형상변수인 시험편의 길이와 폭의 비(L/W), 평균곡률반경과 두께의 비($R_m/t$)에 대한 파괴인성시험 후, ASTM 시험법에서 제시한 표준시험편의 J-적분과 한계하중법으로 구한 J-적분을 각각 적용하여 구한 파괴저항곡선을 평가하였다. 또한 배관의 파괴저항곡선을 잘 모사한다고 알려진 휨 광폭평판(CWP) 및 표준시험편의 파괴저항곡선과 비교 고찰하여 최종적으로 Curved CT 시험편의 파괴저항곡선에 대한 유효성을 평가하였다. 본 논문의 결과는 향후 실배관의 정확한 파괴인성을 평가하는 데 있어 Curved CT 시험편의 적용가능성을 평가하는 데에 활용할 수 있다.

Keywords

References

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