Journal of the Earthquake Engineering Society of Korea (한국지진공학회논문집)

Earthquake Engineering Society of Korea (한국지진공학회)
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Generation of Floor Response Spectra Considering Coupling Effect of Primary and Secondary System

부구조시스템의 연계 효과를 고려한 구조물의 층응답 스펙트럼 생성

  • Cho, Sung Gook (R&D Center, Innose Tech Co. Ltd.) ;
  • Gupta, Abhinav (Center for Nuclear Energy Facilities and Structures (CNEFS), NC State University)
  • Received : 2020.03.16
  • Accepted : 2020.05.06
  • Published : 2020.07.01
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Abstract

Seismic qualification of equipment including piping is performed by using floor response spectra (FRS) or in-structure response spectra (ISRS) as the earthquake input at the base of the equipment. The amplitude of the FRS may be noticeably reduced when obtained from coupling analysis because of interaction between the primary structure and the equipment. This paper introduces a method using a modal synthesis approach to generate the FRS in a coupled primary-secondary system that can avoid numerical instabilities or inaccuracies. The FRS were generated by considering the dynamic interaction that can occur at the interface between the supporting structure and the equipment. This study performed a numerical example analysis using a typical nuclear structure to investigate the coupling effect when generating the FRS. The study results show that the coupling analysis dominantly reduces the FRS and yields rational results. The modal synthesis approach is very practical to implement because it requires information on only a small number of dynamic characteristics of the primary and the secondary systems such as frequencies, modal participation factors, and mode shape ordinates at the locations where the FRS needs to be generated.

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References

  1. EPRI. Seismic Evaluation Guidance: Screening, Prioritization, and Implementation Details (SPID) for the Resolution of Fukushima Near-Term Task Force Recommendation 2.1: Seismic. Technical Report # 1025287, Electric Power Research Institute. c2012.
  2. Gupta A, Cho SG, Hong KJ, Han M. Current state of in-cabinet response spectra for seismic qualification of equipment in nuclear power plants. Nuclear Engineering and Design. 2019;343:269-275. https://doi.org/10.1016/j.nucengdes.2018.12.017
  3. Cho SG, Kim D, Chaudhary S. A simplified model for nonlinear seismic response analysis of equipment cabinets in nuclear power plants. Nuclear Engineering and Design. 2011;241(8):2750-2757. https://doi.org/10.1016/j.nucengdes.2011.06.026
  4. Huang Y, Whittaker AS, Luco N. A probabilistic seismic risk assessment procedure for nuclear power plants: (I) Methodology. Nuclear Engineering and Dessign. 2011;241(9):3996-4003. https://doi.org/10.1016/j.nucengdes.2011.06.051
  5. Huang Y, Whittaker AS, Luco N. A probabilistic seismic risk assessment procedure for nuclear power plants: (II) Application. Nuclear Engineering and Design. 2011;241(9):3985-3995. https://doi.org/10.1016/j.nucengdes.2011.06.050
  6. Rydell C, Malm R, Ansell A. Piping system subjected to seismic hard rock high frequencies. Nuclear Engineering and Design. 2014; 278:302-309. https://doi.org/10.1016/j.nucengdes.2014.07.009
  7. Gupta A, Bose M. Significance of non-classical damping in seismic qualification of equipment and piping. Nuclear Engineering and Design. 2017;317:90-99. https://doi.org/10.1016/j.nucengdes.2017.03.020
  8. Xu J. DeGrassi G. Benchmark Program for the Evaluation of Methods to Analyze Non-Classically Damped Coupled Systems. NUREG/CR-6661, US Nuclear Regulatory Commission / Brookhaven National Laboratory. c2000.
  9. Gupta A, Gupta AK. New developments in coupled seismic analysis of equipment and piping. Proceedings of the 13th International Conference on Structural Mechanics in Reactor Technology. Porto Alegre, Brazil. c1995.
  10. Gupta A, Gupta AK. Applications of new developments in coupled seismic analysis of piping systems. Proceedings of the 13th International Conference on Structural Mechanics in Reactor Technology. Porto Alegre, Brazil. c1995.
  11. Kelly JM, Marsico MR. The influence of damping on floor spectra in seismic isolated nuclear structures. Structural Control Health Monitoring. 2015;22:743-756. https://doi.org/10.1002/stc.1715
  12. Firoozabad ES, Jeon B, Coi HS, Kim NS. Seismic fragility analysis of seismically isolated nuclear power plants piping system. Nuclear Engineering and Design. 2015;284:264-279. https://doi.org/10.1016/j.nucengdes.2014.12.012
  13. Li B, Jiang W, Xie W, Pandey MD. Generate floor response spectra, Part 2: response spectra for equipment-structure resonance. Nuclear Engineering and Design. 2015;293:547-560. https://doi.org/10.1016/j.nucengdes.2015.05.033
  14. Gupta AK. Response Spectrum Method in Seismic Analysis and Design of Structures. Blackwell Scientific Publications, Inc. ISBN 0-8493-8628-4. c1990.
  15. Wang X, Xia Z. Seismic Resistant Analysis of Coupled Model of Reactor Coolant System and Reactor Building. Transactions of the 17th International Conference on Structural Mechanics in Reactor Technology. Beijing, China. c2005.
  16. SAP2000. CSI. Computers and Structures Inc. Berkeley, CA, USA. c2013.
  17. U.S. Nuclear Regulatory Commission. Regulatory Guide 1.60, Design Response Spectra for Seismic Design of Nuclear Power Plants, US NRC, Washington, D.C., United States, Revision 2. c2014.