Journal of the Earthquake Engineering Society of Korea (한국지진공학회논문집)

Earthquake Engineering Society of Korea (한국지진공학회)
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Development of Drift-Based Fragility Functions for WUF-W Moment Connection

WUF-W 모멘트 접합부의 변위비 기반 취약도 함수 개발

  • Lee, UiJae (Department of Architectural Engineering, Hanyang University) ;
  • Cho, EunSeon (Department of Architectural Engineering, Hanyang University) ;
  • Han, Sang Whan (Department of Architectural Engineering, Hanyang University)
  • 이의재 (한양대학교 건축공학과) ;
  • 조은선 (한양대학교 건축공학과) ;
  • 한상환 (한양대학교 건축공학과)
  • Received : 2024.10.03
  • Accepted : 2024.10.21
  • Published : 2024.11.01
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Abstract

Steel moment frame connections are vital in moment frames designed to resist forces transferred from adjoining beams and columns. The welded unreinforced flange-welded web (WUF-W) connection is one of the pre-qualified connections used for steel special moment frames (SMFs). This study developed drift-based fragility functions for WUF-W connections based on test data of 35 WUF-W connection specimens from ten previous experimental studies. Four different damage states were defined to calculate the fragility: onset of yielding, local buckling, strength loss, and fracture. Fragility functions were derived assuming that lognormal distribution was validated using the Kolmogorov-Smirnov (K-S) test. It was confirmed that fragility functions for WUF-W connections were accurately proposed within a specified confidence interval. The fragility functions proposed in this study exhibit smaller standard deviations compared to FEMA P58, thereby reducing the likelihood of overestimating or underestimating damage at specific drift ratios. Furthermore, these functions remain within the confidence intervals across all damage states, contributing to improved accuracy in damage analysis and loss estimation in performance-based earthquake engineering.

Keywords

Acknowledgement

본 논문은 한국연구재단 과제(2020R1A2C2010548) 연구의 일환으로 수행되었음.

References

  1. Ricles JM, Mao C, Lu LW, Fisher JW. Inelastic cyclic testing of welded unreinforced moment connections. J Struct Eng. 2002; 128(4):429-440.
  2. Lee D, Cotton SC, Hajjar JF, Dexter RJ, Ye Y. Cyclic behavior of steel moment-resisting connections reinforced by alternative column stiffener details I. Engineering Journal. 2005;42(4):189-214.
  3. Lee D, Cotton SC, Hajjar JF, Dexter RJ, Ye Y. Cyclic behavior of steel moment-resisting connections reinforced by alternative column stiffener details II. Engineering Journal. 2005;42(4):215-238.
  4. AISC 358. Prequalified connections for special and intermediate steel moment frames for seismic applications, including supplement No.1. Chicago, IL: American Institute of Steel Construction; c2022.
  5. Ghobarah A. Performance-based design in earthquake engineering: state of development. Eng Struct. 2001;23(8):878-884.
  6. Moehle J, Deierlein GG. A framework methodology for performance-based earthquake engineering. In 13th world conference on earthquake engineering; 2004 Aug 1-6; Vancouver, B.C., Canada; 13 WCEE Secretariat; c2004 679-691.
  7. Porter KA. An overview of PEER's performance-based earthquake engineering methodology. In Proceedings of ninth international conference on applications of statistics and probability in civil engineering. 2003 Jul;1-8.
  8. Hwang SH, Mangalathu S, Jeon JS. Quantifying the effects of long-duration earthquake ground motions on the financial losses of steel moment resisting frame buildings of varying design risk category. Earthq Eng Struct Dyn. 2021;50(5):1451-1468.
  9. ASCE 7. Minimum design loads and associated criteria for buildings and other structures. Reston, VA: American Society of Civil Engineers; c2022.
  10. ASCE 41. Seismic evaluation and retrofit of existing buildings. Reston, VA: American Society of Civil Engineers; c2023.
  11. FEMA P58. Seismic performance assessment of buildings. Washington, DC: Federal Emergency Management Agency; c2012.
  12. Jones S L, Fry GT, Engelhardt MD. Experimental evaluation of cyclically loaded reduced beam section moment connections. J Struct Eng. 2002;128(4):441-451.
  13. Zhang X, Ricles JM. Seismic behavior of reduced beam section moment connections to deep columns. J Struct Eng. 2006;132(3): 358-367.
  14. Johnson J, Sarif N. Seismic performance of fire exposed steel welded WUF-W and RBS connections. In IOP Conference Series: Earth and Environmental Science. 2020 June;491(1):012-030.
  15. Han SW, Kwon GU, Moon KH. Cyclic behaviour of post-Northridge WUF-B connections. J Constr Steel Res. 2007;63(3):365-374.
  16. Han SW, Moon KH, Kim JM, Histeretic behavior of Welded Unreinforced Flange-Welded web (WUF-W) connections with high-performance steel column under cyclic loading. Journal of the Architectural Institute of Korea Structure & Construction. 2011; 27(7):57-64.
  17. Han SW, Moon KH, Jung J. Cyclic performance of welded unreinforced flange-welded web moment connections. Earthquake Spectra. 2014; 30(4):1663-1681.
  18. Han SW, Jung J, Ha SJ. Seismic performance of WUF-W moment connections according to access hole geometries. Earthquake Spectra. 2016;32(2):909-926.
  19. Shin S. Experimental and analytical investigation of panel zone behavior in steel moment frames. Doctoral dissertation; c2017.
  20. Reynolds M, Uang CM. Economical weld details and design for continuity and doubler plates in steel special moment frames. J Struct Eng. 2022;148(1):04021246.
  21. Tapia-Hernandez E, Santiago-Flores A, Guerrero-Bobadilla H. Performance of seismic steel beam-column moment joints. Bull Earthquake Eng. 2022;20(12):6741-6761.
  22. Skiadopoulos A, Lignos DG, Arita M, Hiroshima S. Full-Scale Experiments of Cyclically Loaded Welded Moment Connections with Highly Dissipative Panel Zones and Simplified Weld Details. J Struct Eng. 2023;149(12):04023167.
  23. Lignos DG, Kolios D, Miranda E. Fragility assessment of reduced beam section moment connections. J Struct Eng. 2010;136(9): 1140-1150.
  24. Elkady A, Ghimire S, Lignos DG. Fragility curves for wide-flange steel columns and implications for building-specific earthquake-induced loss assessment. Earthquake Spectra. 2018;34(3):1405-1429.
  25. AISC 341. Seismic provisions for structural steel buildings. Chicago, IL: American Institute of Steel Construction; c2022.
  26. Chauvenet W. Spherical and Practical Astronomy. Lippincott: c1863.
  27. Benjamin JR, Cornell CA. Probability, statistics, and decision for civil engineers. Courier Corporation, New York: McGraw-Hill; c1970.
  28. Ramirez CM, Lignos DG, Miranda E, Kolios D. Fragility functions for pre-Northridge welded steel moment-resisting beam-to-column connections. Eng Struct. 2012;45:574-584.
  29. Crow EL, Davis FA, Maxfield MW. Statistics manual, Dover, New York; c1960.