DOI QR코드

DOI QR Code

Limit State Evaluation of Elbow Components Connected with Flexible Groove Joints

유동식 그루브 조인트로 연결된 엘보 요소의 한계상태 평가

  • Sung-Wan Kim ;
  • Da-Woon Yun ;
  • Bub-Gyu Jeon ;
  • Dong-Uk Park ;
  • Sung-Jin Chang (Seismic Research and Test Center, Pusan National University)
  • 김성완 (부산대학교 지진방재연구센터) ;
  • 윤다운 (부산대학교 지진방재연구센터) ;
  • 전법규 (부산대학교 지진방재연구센터) ;
  • 박동욱 (부산대학교 지진방재연구센터) ;
  • 장성진 (부산대학교 지진방재연구센터)
  • Received : 2024.05.30
  • Accepted : 2024.06.14
  • Published : 2024.06.30

Abstract

Piping systems are crucial facilities used in various industries, particularly in areas related to daily life and safety. Piping systems are fixed to the main structures of buildings and facilities but do not support external loads and serve as non-structural elements performing specific functions. Piping systems are affected by relative displacements owing to phase differences arising from different behaviors between two support points under seismic loads; this can cause damage owing to the displacement-dominant cyclic behavior. Fittings and joints in piping systems are representative elements that are vulnerable to seismic loads. To evaluate the seismic performance and limit states of fittings and joints in piping systems, a high-stroke actuator is required to simulate relative displacements. However, this is challenging because only few facilities can conduct these experiments. Therefore, element-level experiments are required to evaluate the seismic performance and limit states of piping systems connected by fittings and joints. This study proposed a method to evaluate the seismic performance of an elbow specimen that includes fittings and joints that are vulnerable to seismic loads in vertical piping systems. The elbow specimen was created by connecting straight pipes to both ends of a 90° pipe elbow using flexible groove joints. The seismic performance of the elbow specimen was evaluated using a cyclic loading protocol based on deformation angles. To determine the margin of the evaluated seismic performance, the limit states were assessed by applying cyclic loading with a constant amplitude.

배관시스템은 다양한 산업 분야에서 이용되는 중요한 설비이며 생활 및 안전과 관련된 영역에서 사용되고 있다. 배관시스템은 건축물 및 시설의 주요 구조부에 고정되어 있으나 외부 하중을 지지하지 않으며 주어진 고유기능을 수행하는 비구조요소이다. 지진하중으로 인한 배관시스템은 두 지지점 사이의 서로 다른 거동으로 발생하는 위상차로 인한 상대 변위의 영향을 받으며 변위 지배적인 반복거동 때문에 손상이 발생할 가능성이 있다. 배관시스템에서 피팅과 조인트는 지진하중에 취약한 대표적인 요소이다. 배관시스템의 피팅과 조인트에 대한 내진성능과 한계상태를 평가하고자 한다면 상대변위를 모사하기 위한 높은 스트로크를 가지는 엑츄에이터가 필요하나 실험을 수행할 수 있는 설비가 많지 않아 어려움이 있다. 따라서 피팅과 조인트로 연결된 배관시스템의 내진성능과 한계상태를 평가하기 위해서는 요소 단위의 실험이 필요하다. 이 연구에서는 수직배관시스템에서 지진하중에 취약한 요소인 피팅과 조인트를 포함하는 엘보 시험체에 대하여 내진성능을 평가하는 방법을 제시하였다. 엘보 시험체는 90° 배관 엘보의 양단에 직관부를 유동식 그루브 조인트를 이용하여 연결하였다. 엘보 시험체에 대하여 변형각에 기반을 둔 주기하중 프로토콜을 이용하여 내진성능을 평가하였다. 평가된 내진성능에 대한 여유도를 확인하기 위하여 일정한 진폭에 대한 주기하중을 적용하여 한계상태를 평가하였다.

Keywords

Acknowledgement

이 논문은 2022년도 정부(교육부)의 재원으로 한국연구재단의 지원을 받아 수행된 기초연구사업임(No. 2022R1I1A1A01067056).

References

  1. Perrone, D., Calvi, P. M., Nascimbene, R., Fischer, E. C., and Magliulo, G. (2019), Seismic Performance of Non-Structural Elements During the 2016 Central Italy Earthquake, Bulletin of Earthquake Engineering, 17(10), 5655-5677.
  2. Dhakal, R. P. (2010), Damage to Non-Structural Components and Contents in 2010 Darfield Earthquake, Bulletin of the New Zealand Society for Earthquake Engineering, 43(4), 404-411.
  3. Perrone, D., and Filiatrault, A. (2017), Automated Seismic Design of Non-Structural Elements with Building Information Modeling, Automation in Construction, 84, 166-175.
  4. Lanzano, G., Salzano, E., Santucci de Magistris, F., and Fabbrocino, G. (2014), Seismic Vulnerability of Gas and Liquid Buried Pipelines, Journal of Loss Prevention in the Process Industries, 28, 72-78.
  5. O'Rourke, T. D., Stewart, H. E., Gowdy, T. E., and Pease, J. W. (1991), Lifeline and geotechnical aspects of the 1989 Loma Prieta Earthquake, Proceedings of the 2nd International Conference on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics, Missouri University of Science and Technology, Saint Louis, 1601-1612.
  6. Kitaura, M., and Miyajima, M. (1996), Damage to Water Supply Pipelines, Soils and Foundations, 325-333.
  7. Blasi, G., Aiello, M. A., Maddaloni, G., and Pecce, M. R. (2018), Seismic Response Evaluation of Medical Gas and Fire-Protection Pipelines' Tee-Joints, Engineering Structures, 173, 1039-1053.
  8. Han, Z., Ma, D., Hou, B., and Wang, W. (2020), Seismic Resilience Enhancement of Urban Water Distribution System Using Restoration Priority of Pipeline Damages, Sustainability, 12(3), 914.
  9. Soroushian, S., Zaghi, A. E., Maragakis, E. M., Echevarria, A., Tian, Y., and Filiatrault, A. (2015), Seismic Fragility Study of Fire Sprinkler Piping Systems with Grooved Fit Joints, Journal of Structural Engineering, 141(6), 04014157.
  10. Kim, S. W., Yun, D. W., Cheung, J. H., and Kim, S. D. (2020), Limit State Assessment of SCH80 3-inch Steel Pipe Elbows Using Moment-Deformation Angle Relationship, Journal of the Korea Institute for Structural Maintenance and Inspection, 24(3), 122-129 (in Korean).
  11. Kim, S. W. , Yun, D. W. , Kim, J. B. , and Jeon, B. G. (2021), Experimental Study for Seismic Behavior Analysis of a Fire Protection Riser Pipe System with Groove Joints, Journal of the Korea Institute for Structural Maintenance and Inspection, 25(2), 35-42 (in Korean).
  12. National Fire Protection Association(NFPA) (2013), Standard for the Installation of Sprinkler Systems(NFPA 13), NFPA, Quincy, USA.
  13. Ministry of Public Safety and Security(MPSS) (2016), Seismic Design Criteria of Fire Fighting Facilities, Sejong, Korea.
  14. American Society of Civil Engineers(ASCE)/Structural Engineering Institute(SEI) (2016), Minimum Design Loads for Buildings and Other Structures (ASCE 7-16), ASCE/SEI, Reston, USA.
  15. American National Standards Institute(ANSI) (2016), American National Standard for Seismic Sway Braces for Pipe, Tubing and Conduit(ANSI/FM Approvals 1950), FM Approvals, Norwood, USA.