利用强震记录分析场地的地震反应
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摘要
利用唐山近场强震记录对如何分析场地反应进行研究 ,分析比较了多种方法 :线性反演法、传统的谱比法以及接收函数法 .通过比较研究 ,发现各种方法都能给出土层场地的卓越周期 ,但每种方法给出的场地反应不完全相同 .其中 ,传统的谱比法与线性反演法的结果较为接近 ,而接收函数法的结果则同其它两种方法的结果相差较大 .在线性反演法中 ,给出了 S波的品质因子 QS,QS在 0 .5～ 32 Hz范围内与频率有关 :QS(f) =67f1 .
A seismic observation array for strong motions was deployed to estimate seismic source, propagation path and local site effects in Tangshan, China. We compared site response from the S wave inversion and those from other techniques, such as traditional direct spectral ratios of S waves and receiver function of S waves. From the inversion, we found that S wave quality factor, i.e. Q S value, is approximately satisfied with the relation of Q S=67 f 1.1 in the range of frequency from 0.5 to 32 Hz and that the source spectra follow the ω -2 model of seismic source for low frequencies less than about 12 Hz. From the comparison of site responses estimated by the different methods for each soil site, we found that all the methods can extract the same predominant peaks from the responses, the amplifications from direct S wave spectral ratios are well correlated with those from the S wave inversion within a factor of 2 to 3, while the correlation between the amplifications from S wave receiver function and those from the S wave inversion is not good, especially for high frequencies more than 8 Hz.
A seismic observation array for strong motions was deployed to estimate seismic source, propagation path and local site effects in Tangshan, China. We compared site response from the S wave inversion and those from other techniques, such as traditional direct spectral ratios of S waves and receiver function of S waves. From the inversion, we found that S wave quality factor, i.e. Q S value, is approximately satisfied with the relation of Q S=67 f 1.1 in the range of frequency from 0.5 to 32 Hz and that the source spectra follow the ω -2 model of seismic source for low frequencies less than about 12 Hz. From the comparison of site responses estimated by the different methods for each soil site, we found that all the methods can extract the same predominant peaks from the responses, the amplifications from direct S wave spectral ratios are well correlated with those from the S wave inversion within a factor of 2 to 3, while the correlation between the amplifications from S wave receiver function and those from the S wave inversion is not good, especially for high frequencies more than 8 Hz.
引文
AndrewsD J.1982.Separation of source and propagation spectra ofsevenMammothLakes aftershocks[A].ProceedingsofWorkshop,Dynamic characteristicsof faulting,1981.U.S GeolSurOpenFileRep,82～591
BorcherdtR D.1970.Effects of local geology on ground m otion nearSanFranciscoBay[J].BullSeismSocAmer,60:29～61
BorcherdtR D,GibbsF J.1976.Effects of local geological conditions in the region on ground motions and intensities of the1906 earthquakes[J].BullSeismSocAmer,66:467～500
HartzellS H.1992.Site response estimation from earthquake data[J].BullSeimSocAmer,82:2308～2327
HaskellN A.1966.Total energy and energy spectral density of elastic wave radiation from propagation faultsII[J].BulSeismSocAmer,56:125～140
IwataT,Irikura k.1986.Separation ofsource,propagation and site effects from observedS- waves[J].Zisin,39:579～593(inJapanese)
LangstonC A.1977.Corvallis,Oregon,crustal and upperm antle receiverstructurefrom teleseism icP andS waves[J].BullSeismSocAmer,67:713～724
LangstonC A .1979.Structure underMountRainier,Washington,inferred from teleseismic body waves[J].J GeophysRes,84:4749～4762
LawsonC L,HansonR.1974.SolvingLeastSquaresProblems[M].NewJersey:Prentice-Hall,Inc.EnglewoodCliffs,18～21
BorcherdtR D.1970.Effects of local geology on ground m otion nearSanFranciscoBay[J].BullSeismSocAmer,60:29～61
BorcherdtR D,GibbsF J.1976.Effects of local geological conditions in the region on ground motions and intensities of the1906 earthquakes[J].BullSeismSocAmer,66:467～500
HartzellS H.1992.Site response estimation from earthquake data[J].BullSeimSocAmer,82:2308～2327
HaskellN A.1966.Total energy and energy spectral density of elastic wave radiation from propagation faultsII[J].BulSeismSocAmer,56:125～140
IwataT,Irikura k.1986.Separation ofsource,propagation and site effects from observedS- waves[J].Zisin,39:579～593(inJapanese)
LangstonC A.1977.Corvallis,Oregon,crustal and upperm antle receiverstructurefrom teleseism icP andS waves[J].BullSeismSocAmer,67:713～724
LangstonC A .1979.Structure underMountRainier,Washington,inferred from teleseismic body waves[J].J GeophysRes,84:4749～4762
LawsonC L,HansonR.1974.SolvingLeastSquaresProblems[M].NewJersey:Prentice-Hall,Inc.EnglewoodCliffs,18～21
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