近断层地震动的频谱周期参数和非平稳特征分析
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摘要
分析地震动的频谱周期参数和频率非平稳特征,是地震危险性分析和结构抗震设计的重要内容。本文对近断层地震动记录按照不同的运动特征分组,进行了Hilbert-Huang变换分析。结合相关的定义得到了表征地震动频谱特性的7个周期参数,包括:Fourier幅值谱平均周期Tm、Hilbert边际谱平均周期Tmh、特征周期Tc、卓越周期等,并计算了地震动的Hilbert谱瞬时频率时程变异系数。计算结果表明,从整体上把握地震动频谱特性的三个周期参数Tm、Tmh和Tc适合于表征近断层地震动的频谱成份。近断层地震动的频率非平稳特征显著,Hilbert谱瞬时频率变异系数良好地反映了地震动的频率非平稳性质和程度。而且,考察了近断层地震动运动特征对地震动频谱周期参数和频率非平稳性的影响。
Analyzing the frequency content parameters and non-stationary property of earthquake ground motions is an important topic of seismic hazard assessment and structural seismic design.The near-fault ground motion recordings are divided into several groups according to their motion characteristics.Hilbert-Huang transform is implemented for these ground motions.Then,seven frequency content parameters of ground motions are obtained including the mean period of Fourier amplitude spectra Tm,mean period of Hilbert marginal spectra Tmh,characteristic period Tc and predominant periods and so on according to the related definitions.Furthermore,the variance coefficients of instantaneous frequency time histories of Hilbert spectra are calculated.Numerical results indicate that three period parameters Tm,Tmh and Tc are suitable for characterizing the frequency content of near-fault ground motions.The non-stationary characteristic of frequency content of near-fault ground motions is remarkable,and the variance coefficients of instantaneous frequency of Hilbert spectra can reflect well the non-stationary property and degree of ground motions.Moreover,the influence of motion characteristics of near-fault ground motions on their frequency content parameters and nonstationarity is examined.
Analyzing the frequency content parameters and non-stationary property of earthquake ground motions is an important topic of seismic hazard assessment and structural seismic design.The near-fault ground motion recordings are divided into several groups according to their motion characteristics.Hilbert-Huang transform is implemented for these ground motions.Then,seven frequency content parameters of ground motions are obtained including the mean period of Fourier amplitude spectra Tm,mean period of Hilbert marginal spectra Tmh,characteristic period Tc and predominant periods and so on according to the related definitions.Furthermore,the variance coefficients of instantaneous frequency time histories of Hilbert spectra are calculated.Numerical results indicate that three period parameters Tm,Tmh and Tc are suitable for characterizing the frequency content of near-fault ground motions.The non-stationary characteristic of frequency content of near-fault ground motions is remarkable,and the variance coefficients of instantaneous frequency of Hilbert spectra can reflect well the non-stationary property and degree of ground motions.Moreover,the influence of motion characteristics of near-fault ground motions on their frequency content parameters and nonstationarity is examined.
引文
[1]Rathje E M,Abrahamon NA,Bray J D.Simplified frequency content estimates of earthquake ground motions[J].Journal of Geotechnical Engi-neering,1998,124(2):150-159.
[2]Rathje E M,Faraj F,Russell S,et al.Empirical relationship for frequency content parameters of earthquake ground motions[J].EarthquakeSpectra,2004,20(1):119-144.
[3]徐龙军,谢礼立.集集地震近断层地震动频谱特性[J].地震学报,2005,27(6):656-665.
[4]董娣,周锡元,徐国栋,等.强震记录频率非平稳特性的若干研究[J].地震工程与工程振动,2006,26(1):22-29.
[5]Kalkan E,Kunnath S K.Effects of fling step and forward directivity on seismic response of buildings[J].Earthquake Spectra,2006,22(2):367-390.
[6]Huang N E,Shen Z,Long L S,et al.The empirical mode decomposition and the Hilbert spectrum for nonlinear and non-stationary time seriesanalysis[J].Proceedings Royal Society of London A,1998,454:903-995.
[7]Huang N E,Chern C C,Huang K,et al.A newspectral representation of earthquake data:Hilbert analysis of station TCU129,Chi-Chi,Tai-wan,21,September 1999[J].Bulletin of the Seismological Society of America,2001,91(5):1310-1338.
[8]Loh C H,Wu TC,Huang NE.Application of the empirical mode decomposition-Hilbert spectrum method to identify near-fault ground-mo-tion characteristics and structural responses[J].Bulletin of the Seismological Society of America,2001,91(5):1339-1357.
[9]Zhang R C,Ma S,Hartzell S.Signatures of seismic source in EMD-based characterization of the 1994 Northridge,California,earthquake re-cordings[J].Bulletin of the Seismological Society of America,2003,93(1):501-518.
[10]胡聿贤,张郁山,梁建文.应用HHT方法从竖向地震动记录识别场地液化的物理过程[J].地震工程与工程振动,2004,24(3):1-11.
[11]Kijewski-Correa T,Kareem A.Efficacy of Hilbert and wavelet transforms for time-frequency analysis[J].Journal of Engineering Mechanics,2006,132(10):1037-1049.
[12]Spanos P D,Giaralis A,Politis N P.Time-frequency representation of earthquake accelerograms and inelastic structural response records usingthe adaptive chirplet decomposition and empirical mode decomposition[J].Soil Dynamics and Earthquake Engineering,2007,27:675-689.
[13]Yang J N,Lei Y,Lin S,et al.Hilbert-Huang based structural damage detection[J].Journal of Engineering Mechanics,2004,130(1):85-95.
[14]Pines D,Salvino L.Structural health monitoring using empirical mode decomposition and the Hilbert phase[J].Journal of Sound and Vibration,2006,294:97-124.
[15]Zhu X Q,LawS S.Nonlinear characteristics of damaged reinforced concrete beamfromHilbert-Huang transform[J].Journal of Structural Engi-neering,2007,133(8):1186-1191.
[16]Chen J,Xu Y L.Modal parameter identification of Tsing Ma suspension bridge under typhoon Victor:EMD-HTmethod[J].Journal of WindEngineering and Industrial Aerodynamics,2004,92(10):805-827.
[17]Varadarajan N,Nagarajaiah S.Wind response control of building with variable stiffness tuned mass damper using empirical mode decompositionand Hilbert transform[J].Journal of Engineering Mechanics,2004,130(4):451-458.
[18]Yang D X,Pan J W,Li G.Non-structure specific intensity measure parameters and characteristic period of near-fault ground motions[J].Earthquake Engineering and Structural Dynamics,2009,38(11):1257-1280.
[19]刘启方,袁一凡,金星,等.近断层地震动的基本特征[J].地震工程与工程振动,2006,26(1):1-10.
[2]Rathje E M,Faraj F,Russell S,et al.Empirical relationship for frequency content parameters of earthquake ground motions[J].EarthquakeSpectra,2004,20(1):119-144.
[3]徐龙军,谢礼立.集集地震近断层地震动频谱特性[J].地震学报,2005,27(6):656-665.
[4]董娣,周锡元,徐国栋,等.强震记录频率非平稳特性的若干研究[J].地震工程与工程振动,2006,26(1):22-29.
[5]Kalkan E,Kunnath S K.Effects of fling step and forward directivity on seismic response of buildings[J].Earthquake Spectra,2006,22(2):367-390.
[6]Huang N E,Shen Z,Long L S,et al.The empirical mode decomposition and the Hilbert spectrum for nonlinear and non-stationary time seriesanalysis[J].Proceedings Royal Society of London A,1998,454:903-995.
[7]Huang N E,Chern C C,Huang K,et al.A newspectral representation of earthquake data:Hilbert analysis of station TCU129,Chi-Chi,Tai-wan,21,September 1999[J].Bulletin of the Seismological Society of America,2001,91(5):1310-1338.
[8]Loh C H,Wu TC,Huang NE.Application of the empirical mode decomposition-Hilbert spectrum method to identify near-fault ground-mo-tion characteristics and structural responses[J].Bulletin of the Seismological Society of America,2001,91(5):1339-1357.
[9]Zhang R C,Ma S,Hartzell S.Signatures of seismic source in EMD-based characterization of the 1994 Northridge,California,earthquake re-cordings[J].Bulletin of the Seismological Society of America,2003,93(1):501-518.
[10]胡聿贤,张郁山,梁建文.应用HHT方法从竖向地震动记录识别场地液化的物理过程[J].地震工程与工程振动,2004,24(3):1-11.
[11]Kijewski-Correa T,Kareem A.Efficacy of Hilbert and wavelet transforms for time-frequency analysis[J].Journal of Engineering Mechanics,2006,132(10):1037-1049.
[12]Spanos P D,Giaralis A,Politis N P.Time-frequency representation of earthquake accelerograms and inelastic structural response records usingthe adaptive chirplet decomposition and empirical mode decomposition[J].Soil Dynamics and Earthquake Engineering,2007,27:675-689.
[13]Yang J N,Lei Y,Lin S,et al.Hilbert-Huang based structural damage detection[J].Journal of Engineering Mechanics,2004,130(1):85-95.
[14]Pines D,Salvino L.Structural health monitoring using empirical mode decomposition and the Hilbert phase[J].Journal of Sound and Vibration,2006,294:97-124.
[15]Zhu X Q,LawS S.Nonlinear characteristics of damaged reinforced concrete beamfromHilbert-Huang transform[J].Journal of Structural Engi-neering,2007,133(8):1186-1191.
[16]Chen J,Xu Y L.Modal parameter identification of Tsing Ma suspension bridge under typhoon Victor:EMD-HTmethod[J].Journal of WindEngineering and Industrial Aerodynamics,2004,92(10):805-827.
[17]Varadarajan N,Nagarajaiah S.Wind response control of building with variable stiffness tuned mass damper using empirical mode decompositionand Hilbert transform[J].Journal of Engineering Mechanics,2004,130(4):451-458.
[18]Yang D X,Pan J W,Li G.Non-structure specific intensity measure parameters and characteristic period of near-fault ground motions[J].Earthquake Engineering and Structural Dynamics,2009,38(11):1257-1280.
[19]刘启方,袁一凡,金星,等.近断层地震动的基本特征[J].地震工程与工程振动,2006,26(1):1-10.
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