TY - JOUR
T1 - Shaking table test and numerical analysis of nuclear piping under low- and high-frequency earthquake motions
AU - Kwag, Shinyoung
AU - Eem, Seunghyun
AU - Kwak, Jinsung
AU - Lee, Hwanho
AU - Oh, Jinho
AU - Koo, Gyeong Hoi
AU - Chang, Sungjin
AU - Jeon, Bubgyu
N1 - Publisher Copyright:
© 2022 Korean Nuclear Society
PY - 2022/9
Y1 - 2022/9
N2 - A nuclear power plant (NPP) piping is designed against low-frequency earthquakes. However, earthquakes that can occur at NPP sites in the eastern part of the United States, northern Europe, and Korea are high-frequency earthquakes. Therefore, this study conducts bi-directional shaking table tests on actual-scale NPP piping and studies the response characteristics of low- and high-frequency earthquake motions. Such response characteristics are analyzed by comparing several responses that occur in the piping. Also, based on the test results, a piping numerical analysis model is developed and validated. The piping seismic performance under high-frequency earthquakes is derived. Consequently, the high-frequency excitation caused a large amplification in the measured peak acceleration responses compared to the low-frequency excitation. Conversely, concerning relative displacements, strains, and normal stresses, low-frequency excitation responses were larger than high-frequency excitation responses. Main peak relative displacements and peak normal stresses were 60%–69% and 24%–49% smaller in the high-frequency earthquake response than the low-frequency earthquake response. This phenomenon was noticeable when the earthquake motion intensity was large. The piping numerical model simulated the main natural frequencies and relative displacement responses well. Finally, for the stress limit state, the seismic performance for high-frequency earthquakes was about 2.7 times greater than for low-frequency earthquakes.
AB - A nuclear power plant (NPP) piping is designed against low-frequency earthquakes. However, earthquakes that can occur at NPP sites in the eastern part of the United States, northern Europe, and Korea are high-frequency earthquakes. Therefore, this study conducts bi-directional shaking table tests on actual-scale NPP piping and studies the response characteristics of low- and high-frequency earthquake motions. Such response characteristics are analyzed by comparing several responses that occur in the piping. Also, based on the test results, a piping numerical analysis model is developed and validated. The piping seismic performance under high-frequency earthquakes is derived. Consequently, the high-frequency excitation caused a large amplification in the measured peak acceleration responses compared to the low-frequency excitation. Conversely, concerning relative displacements, strains, and normal stresses, low-frequency excitation responses were larger than high-frequency excitation responses. Main peak relative displacements and peak normal stresses were 60%–69% and 24%–49% smaller in the high-frequency earthquake response than the low-frequency earthquake response. This phenomenon was noticeable when the earthquake motion intensity was large. The piping numerical model simulated the main natural frequencies and relative displacement responses well. Finally, for the stress limit state, the seismic performance for high-frequency earthquakes was about 2.7 times greater than for low-frequency earthquakes.
KW - Earthquake
KW - High-frequency excitation
KW - Nuclear power plant
KW - Piping
KW - Seismic performance
KW - Seismic response analysis
KW - Shaking table test
UR - http://www.scopus.com/inward/record.url?scp=85133728169&partnerID=8YFLogxK
U2 - 10.1016/j.net.2022.03.039
DO - 10.1016/j.net.2022.03.039
M3 - Article
AN - SCOPUS:85133728169
SN - 1738-5733
VL - 54
SP - 3361
EP - 3379
JO - Nuclear Engineering and Technology
JF - Nuclear Engineering and Technology
IS - 9
ER -