Time-frequency and engineering characteristics on offshore ground motion

PDF(1879 KB)

Journal of Vibration and Shock ›› 2018, Vol. 37 ›› Issue (16) : 227-233.

CHEN Su1, ZHOU Yue1, LI Xiaojun1,2， FU Lei1

Author information +

History +

Abstract

Based on the offshore ground motions recorded in California, U.S, and the Sagami trough zone, Japan, the offshore ground motions time-frequency distribution features were analyzed by the Hilbert-Huang transform method.The acceleration spectrum and dynamic amplification factor β spectrum were compared with the design spectra in relevant seismic design standards.The research results indicate that the offshore ground motions contain a wealth of long period component sand that the long period and ultra-long period components were dominant in frequency range.The normalized marginal spectrum’s energy distribution was correlated with epicenter distance.The horizontal offshore ground motion’s intensity was much greater than that of the vertical ground motion.Moreover, findings show that the dynamic amplification factor β-values of most offshore ground motions are greater than the current platform value of seismic design standards used, which means that their long-period components are much larger than the seismic design standards(i.e., it is risky to use offshore facility seismic design by land seismic design standards).In view of these results, there are many engineering structures such as long-span bridges and oil and gas platforms whose long period components of offshore ground motions warrant more attention in offshore engineering structure seismic design.

Key words

offshore ground motion / seismic design, Hilbert-Huang transform / offshore engineering structure

Cite this article

EndNote

Ris (Procite)

Bibtex

Download Citations

CHEN Su1, ZHOU Yue1, LI Xiaojun1,2， FU Lei1. Time-frequency and engineering characteristics on offshore ground motion[J]. Journal of Vibration and Shock, 2018, 37(16): 227-233

References

[1] 李小军. 海域工程场地地震安全性评价的特殊问题[J]. 震灾防御技术, 2006,1(2),97-104.
Li Xiao-jun. Special problems in seismic safety evaluation of sea area engineering site [J]. Technology for earthquake disaster prevention, 2006,1(2),97-104.
[2] Diao H, Hu J, Xie L. Effect of seawater on incident plane P and SV waves at ocean bottom and engineering characteristics of offshore ground motion records off the coast of southern California, USA[J]. Earthquake Engineering and Engineering Vibration, 2014, 13(2): 181-194.
[3] Bruneau M. Preliminary report of structural damage from the Loma Prieta (San Francisco) earthquake of 1989 and pertinence to Canadian structural engineering practice[J]. Canadian Journal of Civil Engineering, 1990, 17(2): 198-208.
[4] Tanaka Y. The 1995 great Hanshin Earthquake and liquefaction damages at reclaimed lands in Kobe Port[J]. International Journal of Offshore and Polar Engineering, 2000, 10(1): 64–72
[5] Hommert P J. Seafloor earthquake measurement system[R]. Quarterly Report, Sandia National Laboratories, Albuquerque, New Mexico, 1987.
[6] Sleefe G E. The long-term measurement of strong-motion earthquakes offshore southern California[C]//Offshore Technology Conference. Offshore Technology Conference, 1990.
[7] Boore D M, Smith C E. Analysis of earthquake recordings obtained from the Seafloor Earthquake Measurement System (SEMS) instruments deployed off the coast of southern California[J]. Bulletin of the Seismological Society of America, 1999, 89(1): 260-274.
[8] Smith C E, Robert M. Development of a probabilistic seismic hazard analysis for offshore facilities in the Santa Barbara Channel[C]//Proceedings of the Joint Meeting of the US-Japan Cooperative Program in Natural Resources Panel on Wind and Seismic Effects. 1999, 31: 140-155.
[9] Hatayama K. Theoretical evaluation of effects of sea on seismic ground motion[C]//Proceedings of the 13th World Conference on Earthquake Engineering. 2004.
[10] Nakamura T, Takenaka H, Okamoto T, et al. FDM Simulation of Seismic‐Wave Propagation for an Aftershock of the 2009 Suruga Bay Earthquake: Effects of Ocean‐Bottom Topography and Seawater Layer[J]. Bulletin of the Seismological Society of America, 2012, 102(6): 2420-2435.
[11] 胡进军, 刁红旗, 谢礼立. 海底强地震动观测及其特征的研究进展[J]. 地震工程与工程振动, 2013, 33(006): 1-8.
HU Jin-jun, DIAO Hong-qi, XIE Li-li. Review of observation and characteristics of seafloor strong motion[J]. Earthquake Engineering and Engineering Vibration, 2013, 33(006): 1-8.
[12] 周越，陈苏，李小军. 基于小波方法的近海域地震动时频特性分析[J]. 土木工程学报, 2016, 49(s1): 7-12.
ZHOU Yue, CHEN Su, LI Xiaojun. Wavelet-based time-frequency charateristic analysis on offshore ground motion[J]. China civil engineering journal, 2016, 49(s1): 7-12.
[13] Chen B, Wang D, Li H, et al. Characteristics of Earthquake Ground Motion on the Seafloor[J]. Journal of Earthquake Engineering, 2015, 19(6): 874-904.
[14] 陈宝魁, 王东升, 李宏男, 等. 海底地震动特性及相关谱研究[J]. 防灾减灾工程学报, 2016 (1): 38-43.
Chen B, Wang D, Li H, et al. Study on the characteristics of offshore ground motion and its response spectra[J]. Journal of Disaster Prevention and Mitigation Engineering, 2016 (1): 38-43.
[15] Eguchi T, Fujinawa Y, Fujita E, et al. A real-time observation network of ocean bottom seismometers deployed at the Sagami trough subduction zone, central Japan[J]. Marine Geophysical Researches, 1998, 20(2): 73-94.
[16] 吕悦军, 彭艳菊, 施春花, 等. 渤海海底表层软弱土特征及其对地震动的影响[J]. 防灾减灾工程学报, 2008, 28(3): 368-374.
LU Yue-jun, PENG Yan-ju, SHI Chun-hua. Characteristics of submerged soft soil in the Bohai sea and its influence on ground motion [J]. Journal of disaster prevention and mitigation engineering, 2008, 28(3): 368-374.
[17] Huang N E, Shen Z, Long S R, et al. The empirical mode decomposition and the Hilbert spectrum for nonlinear and non-stationary time series analysis[C]//Proceedings of the Royal Society of London A: Mathematical, Physical and Engineering Sciences. The Royal Society, 1998, 454(1971): 903-995.
[18] 李慧梅, 安钢, 黄梦. 基于局部均值分解的边际谱在滚动轴承故障诊断中的应用[J]. 振动与冲击, 2014, 33(3): 5-8.
LI Hui-jun, AN Gang, HUANG Meng. Application of marginal spectrum based on local mean decomposition in rolling bearing fault diagnosis[J]. Journal of vibration and shock, 2014, 33(3): 5-8.
[19] 谢礼立, 周雍年, 胡成祥, 等. 地震动反应谱的长周期特性[J]. 地震工程与工程振动, 1990, 10(1): 1-20.
XIE Li-li, ZHOU Yong-nian, HU Cheng-xiang, et al. Long period characteristics of ground motion response spectra[J]. Earthquake Engineering and Engineering Vibration,1990, 10(1): 1-20.
[20] 彭艳菊, 吕悦军, 徐杰, 等. 渤海地区地震危险性特征及对工程抗震设防的启示[J]. 地球物理学进展, 2012, 27(1): 18-28.
PENG Yan-ju, LU Yue-jun, XU Jie, et al. Seismic risk zoning in Bohai and its inspiration to engineering earthquake resistance[J]. Progress in Geophysics, 2012, 27(1): 18-28.
[21] 彭艳菊. 基于渤海地震环境的海洋平台抗震设防标准研究[D]. 中国地质大学 (北京), 2008.
PENG Yan-ju. Study on seismic fortification of offshore platform based on the seismic environment of Bohai[D]. China University of Geosciences(Beijing), 2008.
[22] 周雍年, 周正华, 于海英. 设计反应谱长周期区段的研究[J]. 地震工程与工程振动, 2004, 24(2): 15-18.
ZHOU Yong-nian, ZHOU Zheng-hua, YU Hai-Ying. Study on the design of long period section of response spectrum [J]. Earthquake Engineering and Engineering Vibration, 2004, 24(2): 15-18.
[23] Noguchi S, Maeda T, Furumura T. Ocean-influenced Rayleigh waves from outer-rise earthquakes and their effects on durations of long-period ground motion[J]. Geophysical Journal International, 2016, 205(2): 1099-1107.