한국구조물진단유지관리공학회 논문집 (Journal of the Korea institute for structural maintenance and inspection)

  • 제26권4호
  • /
  • Pages.30-39
  • /
  • 2022
  • /
  • 2234-6937(pISSN)
  • /
  • 2287-6979(eISSN)
한국구조물진단유지관리공학회 (Korea Institute for Structural Maintenance Inspection)
권호 표지
DOI QR코드

DOI QR Code

강재 배관 Tee의 한계상태 평가를 위한 손상지수의 적용

Application of Damage Index for Limit State Evaluation of a Steel Pipe Tee

  • 김성완 (부산대학교 지진방재연구센터) ;
  • 윤다운 (부산대학교 지진방재연구센터) ;
  • 전법규 (부산대학교 지진방재연구센터) ;
  • 김성도 (경성대학교 토목공학과)
  • 투고 : 2022.06.14
  • 심사 : 2022.08.19
  • 발행 : 2022.08.30
PDF 다운로드
⟨ 이전 논문 다음 논문 ⟩

초록

원자력발전소 주요기기의 건전성 유지는 구조물의 안전성과 관련하여 매우 중요한 문제로 인식되고 있으며 배관시스템의 건전성은 원자력발전소의 안전과 관련된 매우 중요한 문제이다. 지진하중으로 인한 배관시스템의 실제 파괴모드는 피로균열에 의한 누수이며 구조적인 손상 메커니즘은 소성변형을 발생할 수 있는 큰 상대변위로 인한 저주기 피로이다. 이 연구에서는 원자력발전소의 배관시스템에서 3인치의 강재 직관과 강재 배관 Tee로 구성된 시험체에 대하여 다양한 크기의 일정한 진폭에 대하여 면내반복가력실험을 수행하였다. 지진하중으로 인한 배관시스템에서 발생하는 상대변위를 고려하기 위하여 하중진폭을 증가시켰으며, 강재 배관 Tee의 한계상태인 피로균열에 의한 누수가 발생할 때까지 수행하였다. 힘과 변위의 관계에 대하여 손상모델에 기반을 둔 손상지수를 이용하여 한계상태를 표현하였다. 그 결과 손상지수를 이용하여 강재 배관 Tee의 한계상태를 정량적으로 표현할 수 있음을 확인할 수 있었다.

Maintaining structural integrity of major apparatuses in a nuclear power plant, including piping system, is recognized as a critical safety issue. The integrity of piping system is also a critical matter related to the safety of a nuclear power plant. The actual failure mode of a piping system due to a seismic load is the leakage due to a fatigue crack, and the structural damage mechanism is the low-cycle fatigue due to large relative displacement that may cause plastic deformation. In this study, in-plane cyclic loading tests were conducted under various constant amplitudes using specimens composed of steel straight pipes and a steel pipe tee in the piping system of a nuclear power plant. The loading amplitude was increased to consider the relative displacement generated in the piping system under seismic loads, and the test was conducted until leakage, which is the limit state of the steel pipe tee, occurred due to fatigue cracks. The limit state of the steel pipe tee was expressed using a damage model based on the damage index that used the force-displacement relationship. As a result, it was confirmed that the limit state of the steel pipe tee can be quantitatively expressed using the damage index.

키워드

과제정보

이 성과는 정부(과학기술정보통신부)의 재원으로 한국연구재단의 지원을 받아 수행된 연구임(No. 2021R1A2C1013782).

참고문헌

  1. Surh, H. B., Ryu, T. Y., Park, J. S., Ahn, E. W., Choi, C. S., Koo, J. C., Choi, J. B. and Kim, M. K. (2015), Seismic response analysis of a piping system subjected to multiple support excitations in a base isolated NPP building, Nuclear Engineering and Design, 292, 283-295. https://doi.org/10.1016/j.nucengdes.2015.06.013
  2. Choi, S. Y. and Choi, Y. H. (2004), Piping failure frequency analysis for the main feedwater system in domestic nuclear power plants, Journal of the Korean Nuclear Society, 36(1), 112-120.
  3. Bursi, O. S., Reza, M. S., Abbiati, G. and Paolacci, F. (2015), Performance-based earthquake evaluation of a full-scale petrochemical piping system, Journal of Loss Prevention in the Process Industries, 33, 10-22. https://doi.org/10.1016/j.jlp.2014.11.004
  4. Varelis, G. E., Karamanos, S. A. and Gresnigt, A. M. (2013), Pipe elbows under strong cyclic loading, Journal of Pressure Vessel Technology, 135(1), 011207. https://doi.org/10.1115/1.4007293
  5. Ravi Kiran, A., Reddy, G. R., Agrawal, M. K., Raj, M. and Sajish, S. D. (2019), Ratcheting based seismic performance assessment of a pressurized piping system: Experiments and analysis, International Journal of Pressure Vessels and Piping, 177, 103995. https://doi.org/10.1016/j.ijpvp.2019.103995
  6. Nakamura, I. and Kasahara, N. (2017), Excitation tests on elbow pipe specimens to investigate failure behavior under excessive seismic loads, Journal of Pressure Vessel Technology, 139(6), 061802. https://doi.org/10.1115/1.4037952
  7. Takahashi, K., Ando, K., Matsuo, K. and Urabe, Y. (2014), Estimation of low-cycle fatigue life of elbow pipes considering the multi-axial stress effect, Journal of Pressure Vessel Technology, 136(4), 041405. https://doi.org/10.1115/1.4026903
  8. Kim, S. W., Jeon, B. G., Hahm, D. G. and Kim, M. K. (2020), Ratcheting fatigue failure of a carbon steel pipe tee in a nuclear power plant using the deformation angle, Engineering Failure Analysis, 114, 104595. https://doi.org/10.1016/j.engfailanal.2020.104595
  9. Hasegawa, K., Miyazaki, K. and Nakamura, I. (2008), Failure mode and failure strengths for wall thinning straight pipes and elbows subjected to seismic loading, Journal of Pressure Vessel Technology, 130(1), 011404. https://doi.org/10.1115/1.2826425
  10. Watakabe, T., Tsukimori, K., Kitamura, S. and Morishita, M. (2016), Ultimate strength of a thin wall elbow for sodium cooled fast reactors under seismic loads, Journal of Pressure Vessel Technology, 138(2), 021801. https://doi.org/10.1115/1.4031721
  11. Wang, Z., Pedroni, N., Zentner, I. and Zio, E. (2018), Seismic fragility analysis with artificial neural networks: Application to nuclear power plant equipment, Engineering Structures, 162, 213-225. https://doi.org/10.1016/j.engstruct.2018.02.024
  12. Ma, Q., Kwon, O. S., Kwon, T. H. and Choun, Y. S. (2020), Influence of frequency content of ground motions on seismic fragility of equipment in nuclear power plant, Engineering Structures, 224, 111220. https://doi.org/10.1016/j.engstruct.2020.111220
  13. Koo, G. H., Kwag, S. Y. and Nam, H. S. (2021), Study on inelastic strain-based seismic fragility analysis for nuclear metal components, Energies, 14(11), 3269. https://doi.org/10.3390/en14113269
  14. Udagawa, M., Li, Y., Nishida, A. and Nakamura, I. (2018), Failure behavior analyses of piping system under dynamic seismic loading, International Journal of Pressure Vessels and Piping, 167, 2-10. https://doi.org/10.1016/j.ijpvp.2018.10.002
  15. Harun, M. F., Mohammmad, R. and Kotousov, A. (2020), Low cycle fatigue behavior of elbows with local wall thinning, Metals, 10(2), 260. https://doi.org/10.3390/met10020260
  16. Castiglioni, C. A. and Pucinotti, R. (2009), Failure criteria and cumulative damage models for steel components under cyclic loading, Journal of Constructional Steel Research, 65(4), 751-765. https://doi.org/10.1016/j.jcsr.2008.12.007
  17. Kim, S. W., Yun, D. W., Jeon, B. G. and Kim, S. D. (2021), Damage Index Evaluation Based on Dissipated Energy of SCH 40 3-Inch Carbon Steel Pipe Elbows Under Cyclic Loading, Journal of the Korea Institute for Structural Maintenance and Inspection, 25(1), 112-119. https://doi.org/10.11112/JKSMI.2021.25.1.112
  18. Krawinkler, H. (1987), Performance assessment of steel components, Earthquake spectra, 3(1), 27-41. https://doi.org/10.1193/1.1585417
  19. Gosain, N. K., Brown, R. H. and Jirsa, J. O. (1977), Shear requirements for load reversals on RC members, Journal of the Structural Division, 103(7), 1461-1476. https://doi.org/10.1061/JSDEAG.0004677
  20. Darwin, D. and Nmai, C. K. (1986), Energy dissipation in RC beams under cyclic load, Journal of Structural Engineering, 112(8), 1829-1846. https://doi.org/10.1061/(ASCE)0733-9445(1986)112:8(1829)
  21. Castiglioni, C. A. (1999), Failure criteria and cumulative damage models for steel components under low-cycle fatigue, In Proceedings of 17th California Teachers Association Conference, Napoli.
  22. Park, Y. J. and Ang, A. H. S. (1985), Mechanistic seismic damage model for reinforced concrete, Journal of Structural Engineering, 111(4), 722-739. https://doi.org/10.1061/(ASCE)0733-9445(1985)111:4(722)
  23. Park, Y. J., Ang, A. H. S. and Wen, Y. K. (1987), Damage-limiting aseismic design of buildings, Earthquake Spectra, 3(1), 1-26. https://doi.org/10.1193/1.1585416
  24. Banon, H., Biggs, J. M. and Irvine, H. M. (1981), Seismic damage in reinforced concrete frames, Journal of the Structural Division, 107(9), 1719-1729.
  25. Banon, H. and Veneziano, D. (1982), Seismic safety of reinforced concrete members and structures, Earthquake Engineering & Structural Dynamics, 10(2), 179-193. https://doi.org/10.1002/eqe.4290100202
  26. American Society of Mechanical Engineers (2004), ASME Boiler and Pressure Vessel Code, Section VIII, American Society Mechanical Engineers, New York, USA.