Transactions of the Korean Society of Pressure Vessels and Piping (한국압력기기공학회 논문집)

Korean Society of Pressure Vessels and Piping (한국압력기기공학회)
권호 표지
DOI QR코드

DOI QR Code

A Study on Seismic Performance Improvement of Nuclear Piping System through Dynamic Absorber

동흡진기를 사용한 원전 배관계 내진성능 상향에 대한 연구

  • Received : 2018.10.31
  • Accepted : 2018.12.10
  • Published : 2018.12.30
Download PDF
⟨ Previous Next ⟩

Abstract

In this study, the dynamic absorber and the damper are applied to improve the seismic performance of the piping system, and their quantitative effects on the piping system performance are examined. For this purpose, the response performances of piping system applied with the dynamic absorber/damper are compared with those of the original piping system. Firstly, the frequency response analyses of the piping system with the presence or the absence of dynamic absorber/damper are performed and these results are compared. It has been shown that the maximum acceleration response per the frequency of the piping system is considerably reduced by installing the dynamic absorber and the damper. Secondly, the seismic responses of the piping systems with and without dynamic absorber/damper are compared. As a result of the numerical analyses, it is confirmed that key responses are reduced by 17%-63% due to the installation of the dynamic absorber and damper. Finally, as a result of the seismic performance evaluation, it is confirmed that the HCLPF (High Confidence of Low Probability of Failure) seismic performances are increased by 1.22 to 2.70 times with respect to the failure modes with an aid of the dynamic absorber and damper.

Keywords

HGHRB5_2018_v14n2_41_f0001.png 이미지

Fig. 1 Seismic shock absorber: (a) visco-elastic damper, (b) friction damper

HGHRB5_2018_v14n2_41_f0002.png 이미지

Fig. 2 Seismic shock absorber: (a) concept of dynamic absorber, (b) dynamic absorber applied to piping

HGHRB5_2018_v14n2_41_f0003.png 이미지

Fig. 3 Target piping system: (a) conceptual model, (b) FEM model

HGHRB5_2018_v14n2_41_f0004.png 이미지

Fig. 4 Installation location of dynamic absorbers

HGHRB5_2018_v14n2_41_f0005.png 이미지

Fig. 5 Installation location of dampers

HGHRB5_2018_v14n2_41_f0006.png 이미지

Fig. 6 Comparison of frequency response analysis results

HGHRB5_2018_v14n2_41_f0007.png 이미지

Fig. 7 Comparison of directional acceleration response analysis results at DA installation location

HGHRB5_2018_v14n2_41_f0008.png 이미지

Fig. 8 Comparison of maximum combined stresses

HGHRB5_2018_v14n2_41_f0009.png 이미지

Fig. 9 Comparison of reaction forces at the lowest support of piping: (a) X-dir., (b) Y-dir., (c) Z-dir.

HGHRB5_2018_v14n2_41_f0010.png 이미지

Fig. 10 Changes in HCLPF regarding maximum combined stresses according to changes in log-standard deviations

Table 1 Results of mode analysis

HGHRB5_2018_v14n2_41_t0001.png 이미지

Table 2 Changes in HCLPF of piping according to installation of dynamic absorbers and dampers

HGHRB5_2018_v14n2_41_t0002.png 이미지

References

  1. KBC 2016, 2016, 건축구조기준, 국토교통부
  2. Bezler, P., Subudhi, M. and Hartzman, M., 1985, "Dynamic Analysis Independent Support Motion Response Spectrum Method," Vol. II, U.S. Nuclear Regulatory Commission, Washington, D.C., NUREG/CR-1677.
  3. Kwag, S., Kwak, J., Lee, H., Oh, J. and Koo, G.-H., 2018, "A Study on Application of Tuned Mass Damper to Piping System under Earthquake," Trans. of the KNS Spring Meeting, Jeju, May 17-18.
  4. Kwag, S., Kwak, J., Lee, H., Oh, J. and Koo, G.-H., 2019, "A Numerical Study on Improvement in Seismic Performance of Nuclear Components by applying Dynamic Absorber," J. Comput. Struct. Eng. Inst. Korea, Accepted for publication in Feb. 2019.
  5. EPRI, 1994, "Methodology for Developing Seismic Fragilities," Electric Power Research Institute, Palo Alto, CA, TR-103959.
  6. Kwag, S., Oh, J., Lee, J.-M., and Ryu, J.-S., 2017, "Bayesian-based seismic margin assessment approach: Application to research reactor," Earthq. Struct., Vol. 12, No. 6, pp. 653-663. https://doi.org/10.12989/EAS.2017.12.6.653