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Several parameters have been proposed in the literature for the evaluation of seismic damage. However, in most cases the correlation between results obtained using these parameters and observed damage in structures has not been satisfactory. A parameter for measuring seismic damage previously proposed by the first author is used in this study to analyse a set of 15 accelerograms recorded in 11 earthquakes experienced in different countries. Results using this parameter are compared to global building damage observed during these earthquakes. The use of the parameter proposed here yields results which are consistent with building damage observed in the earthquakes studied. Copyright © 1999 John Wiley & Sons, Ltd. 相似文献
3.
Vulnerability and risk analysis of monuments in Málaga city’s historical centre (Southern Spain) 总被引：1，自引：1，他引：0
A vulnerability analysis of some historical and monumental buildings in the city of Málaga is presented in this paper. More than twenty of these monuments were severely damaged or completely destroyed due to the large earthquake (I max = VIII–IX) occurred in the Málaga region in October 1680. The vulnerability index methodology has been used in this paper. This technique is based on statistical data from seismic damage caused to Italian monuments for the past 30?years. For each building, vulnerability curves have been obtained and damage grades have been estimated. A comparison has been carried out between the expected damage grades and the damage observed from past earthquakes, in order to check the feasibility of applying this methodology to Spanish monuments. This comparison has been possible due to the fact that detailed seismic damage information exists for monuments in the city of Málaga that still exist today, which is a very uncommon case in Spain. Results show a good consistency between expected and observed damage, especially for the churches type. Two seismic scenarios have been proposed for the city centre, one deterministic and one probabilistic, where 54 historical and modern buildings have been analyzed. Both scenarios show worrying results, especially for the types of churches, chapels and towers, where expected high probabilities of suffering very heavy damage or even collapse have been obtained. It is highly recommended to take the necessary measures, in the hope of trying to avoid the possible damage that can be expected from future earthquakes. 相似文献
4.
High energy release during seismic events induced by mining operation is one of the major dangers perturbing production in underground mines. In this work, temporal changes of seismic event parameters for one of the Rudna Mine (Poland) panels are investigated. The study aim was to find whether the temporal clustering of smaller events in different parameters can be observed before and after the high energy events (Ml?≥?3) in the mining panel. The method chosen for analysis was the study of temporal variation of fractal dimension of the seismic events parameter sets composed from: the interevent epicentral distance (dr), logarithm of seismic energy (lE), and interevent energy coefficient (dlE), which is the absolute difference between logarithms of energy of two consecutive events. Temporal variations study was performed in equivalent dimension (ED) space. The transformation of the seismic source parameters into ED space allowed to estimate and compare the temporal changes of the fractal dimension of different parameter spaces using the same method—correlation fractal dimension, and then easily compare the obtained temporal changes of fractal dimension of different parameter sets. The effect of grouping is expressed by decrease of fractal dimension, which is connected with the similarity of events parameter values. The temporal changes of the fractal dimension of seismicity before the strong induced events would indicate some initiation phase of the process leading to the high energy release. In the case of the studied Rudna Mine panel, the temporal behavior of the fractal dimension values in different parameter spaces before seismic events showed significant changes before three out of four events with CLVD dominant source mechanisms. 相似文献
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核电厂在遭遇超设计基准地震时需要考虑安全停堆,以避免造成核泄漏事故。采用地震动的峰值加速度参数(PGA)作为判别停堆的参数具有一定的局限性,PGA参数不能反映地震动的频谱和持时特征,因而可能引起不必要的停堆。针对此问题,基于我国本土大量实际强震记录,遴选出7种典型的工程相关地震动参数,进而基于地震烈度指标,分析发现地震动的标准累计绝对速度参数能更好地表征地震对核电厂的整体潜在破坏能力,适合作为判别停堆的参数,然后提出两种确定预警参数阈值的方法,最终建议考虑我国强震数据特征的核电厂判别停堆的预警参数阈值,为我国核电厂的地震安全停堆参数的确定提供了参考。 相似文献
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This study analyses the performance of residential buildings in the town of Hveragerði in South Iceland during the 29 May 2008 Mw 6.3 Ölfus Earthquake. The earthquake occurred very close to the town, approximately 3–4 km from it. Ground shaking caused by the earthquake was recorded by a dense strong-motion array in the town. The array provided high-quality three-component ground acceleration data which is used to quantify a hazard scenario. In addition, surveys conducted in the town in the aftermath of the earthquake have provided information on macroseismic intensity at various locations in the town. Detailed information regarding the building stock in the town is collected, and their seismic vulnerability models are created by using building damage data obtained from the June 2000 South Iceland earthquakes. Damage to buildings are then simulated by using the scenario hazard and vulnerability models. Damage estimates were also obtained by conducting a survey. Simulated damage based on the scenario macroseismic intensity is found to be similar to damage estimated from survey data. The buildings performed very well during the earthquake—damage suffered was only 5 % of the insured value on the average. Correlation between actual damage and recorded ground-motion parameters is found to be statistically insignificant. No significant correlation of damage was observed, even with macroseismic intensity. Whereas significant correlation was observed between peak ground velocity and macroseismic intensity, neither of them appear to be good indicators of damage to buildings in the study area. This lack of correlation is partly due to good seismic capacity of buildings and partly due to the ordinal nature of macroseismic intensity scale. Consistent with experience from many past earthquakes, the survey results indicate that seismic risk in South Iceland is not so much due to collapse of buildings but rather due to damage to non-structural components and building contents. 相似文献
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G. F. Karakaisis A. S. Savvaidis C. B. Papazachos 《Pure and Applied Geophysics》2003,160(8):1479-1491
— The time variation of two parameters related to accelerating seismic deformation before strong earthquakes in the Aegean area is examined. The first is the b parameter of the Gutenberg-Richter relation and the second is the curvature parameter C, which is a measure of deviation of the accelerating preshock deformation from a linear time variation of this deformation. Following two different procedures, it was found that the b value exhibits a decreasing trend prior to the oncoming earthquake, in agreement with the results of laboratory experiments and other independent observations. C values also show a decreasing trend before main shocks. These results indicate that such time variations of these parameters can be considered as precursory phenomena of ensuing strong earthquakes. 相似文献
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以编制《中国地震动参数区划图》时所构建的地震潜在震源区模型和地震活动性模型为基本输入,在四川省丹棱县及其周缘地区开展基于阿里亚斯烈度的概率地震危险性分析,计算50年超越概率10%的阿里亚斯烈度(Arias Intensity,Ia)。结果表明:丹棱县及其周缘绝大部分地区的Ia值都在0.11m/s以上,部分地区在0.32m/s甚至0.54m/s以上,具有较高的地震诱发滑坡风险,应当加强人员密集区的地震诱发滑坡危险性评估。根据不同Ia预测方程计算得到的Ia分布有较大差异,因此在计算Ia时应考虑多个Ia预测方程,对最终结果进行加权平均,以减小Ia结果的不确定性。同时还发现Ia值与1.0s的谱加速度具有很好的相关性,这也印证了Ia和1.0s谱加速度与砂土液化的相关性。 相似文献
9.
Estimation of Thomsen＇s anisotropic parameters is very important for accuratetime-to-depth conversion and depth migration data processing. Compared with othermethods, it is much easier and more reliable to estimate anisotropic parameters that arerequired for surface seismic depth imaging from vertical seismic profile （VSP） data, becausethe first arrivals of VSP data can be picked with much higher accuracy. In this study, wedeveloped a method for estimating Thomsen＇s P-wave anisotropic parameters in VTImedia using the first arrivals from walkaway VSP data. Model first-arrival travel times arecalculated on the basis of the near-offset normal moveout correction velocity in VTI mediaand ray tracing using Thomsen＇s P-wave velocity approximation. Then, the anisotropicparameters 0 and e are determined by minimizing the difference between the calculatedand observed travel times for the near and far offsets. Numerical forward modeling, usingthe proposed method indicates that errors between the estimated and measured anisotropicparameters are small. Using field data from an eight-azimuth walkaway VSP in TarimBasin, we estimated the parameters 0 and e and built an anisotropic depth-velocity modelfor prestack depth migration processing of surface 3D seismic data. The results showimprovement in imaging the carbonate reservoirs and minimizing the depth errors of thegeological targets. 相似文献
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In this study, a total of 115,246 ground motions recorded during earthquakes of Moment magnitudes ranging from M_w 5.0 to M_w 9.0 are analyzed statistically. A total of 21 ground motion parameters characterising the recorded acceleration time histories are used in the analysis. Classification of these parameters through statistical correlation is reported and a parameter called "distance from zero-amplitude axis," or dZ-A, is formulated in the principal component space. The ability for dZ-A to rate the damage potentials of strong motion records is evaluated through correlation of dZ-A with Japan Meteorological Agency(JMA) instrumental seismic intensities. This parameter can be used to rate damage potential of any strong motion record irrespective of the magnitude and location of the earthquake. It can also be used in selecting ground motion records of appropriate damage potential in seismic design and probabilistic analysis. 相似文献
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O. V. Pavlenko 《Izvestiya Physics of the Solid Earth》2009,45(10):874-884
For evaluating the parameters of the vibrations of the Earth’s surface in the case of strong earthquakes, which are possible in the future, the regular patterns of the emission and propagation of seismic waves in the North Caucasus regions are investigated. The regional parameters of emission and propagation of seismic waves are evaluated by solution of the inverse problems of stochastic modeling of the accelerograms of the earthquakes, recorded by the seismic station in Sochi. The horizontal components of the strongest earthquakes (M w ～ 3.9?5.6), that occurred in 2002–2006 within a radius of ～300 km from the seismic station, with source depths up to 60 km are modeled. For calculations of accelerograms, estimates of the quality are used, obtained earlier for this region in the form: Q(f) ～ 80 ～ f 0.9. The parameter settings are carried out, which determine the shapes of the source spectra, the amplification of the seismic waves in the Earth’s crust, the weakening of the waves at high frequencies (κ), the parameters that determine the shape and duration of accelerograms, etc. Sufficiently good agreement of the calculated and recorded accelerograms is obtained, the regional characteristics of emission and propagation of seismic waves, which can be used for prediction of the parameters of strong motions in the North Caucasus, are evaluated; however, in the future these characteristics should be studied in more detail. 相似文献
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The quantification and prediction of damage due to different seismic actions to structure types of different strength is an important problem not yet solved in the Earthquake Engineering field. In addition, owing to the fact that macroseismic information cannot be used directly in dynamic calculations, a new problem appears when these are the only kind of data available. Thus, there is a need to estimate a parameter to relate the energy of the ground motion and the damage occurrence, and eventually achieve a better seismic risk assessment. After the study and review of some representative potential damage parameters, attention has been paid to the Arias intensity (unfiltered and filtered in certain frequency ranges) and the Cumulative Absolute velocity (CAV) as the parameters to evaluate the energy of movement, and to relate them with the observed damage. The data used to infer these correlations have been provided by the ENEA-ENEL (Italy). The information consists of strong motion records from the Campano Lucano (1980), Umbria (1984) and Lazio-Abruzzo (1984) earthquakes, and data of damage to buildings in the vicinity of recording instruments (within a maximum radius of 300 m, where the soil conditions remain constant). In this paper, some relations have been obtained to quantify the damage level for different seismic inputs. The results suggest that unfiltered Arias intensity and CAV (for calculation threshold 20 cm/s2) correlate well with the macroseismic information used. Best fits are obtained between the quoted parameters and the observed damage in type A structures. © 1997 by John Wiley & Sons, Ltd. 相似文献
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A. A. Lyubushin 《Izvestiya Physics of the Solid Earth》2013,49(1):9-18
The structure of low-frequency seismic noise in the range of periods from 2 min to 500 min is studied from the data of continuous seismic monitoring at 77 seismic stations of the F-net broadband network in Japan from the beginning of 1997 to May 15, 2012. A new statistical characteristic of seismic noise is suggested, namely, the minimal normalized entropy En of the distribution of squared orthogonal wavelet coefficients. This parameter of seismic noise is analyzed in conjunction with the multifractal statistics—the support width of the singularity spectrum, Δα, and the generalized Hurst exponent, α*, which were extensively used by the author in the previous works for analyzing the low-frequency seismic noise. The method for constructing the maps of spatial distribution of Δα, α*, En, and their aggregated normalized value over the time windows with a given length is proposed. The maps are constructed by averaging the succession of the elementary charts, each of which corresponds to a day of observations. It is shown that, for the islands of Japan, the reduction in Δα and α* and the increase in En outline the area of the forthcoming mega earthquake of March 11, 2011, with M = 9 (Tohoku earthquake). According to the analysis of about a year’s worth of data after this event, the region south of Tokyo (Nankai trough) is still dominated by decreased Δα and α* and increased En. This gives grounds to hypothesize that this region remains at a high level of seismic threat since the accumulated stresses were incompletely released by the Tohoku earthquake. Drawing an analogy to the behavior of the coefficient of correlation between Δα and α*, we may suppose that there is an increased probability of a strong earthquake occurring in the second half of 2013 or the first half of 2014. Constructing the averaged maps of the distributions of seismic noise parameters and their aggregated value in a moving time window is suggested as a new method for dynamical assessment of seismic hazards. 相似文献
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Gianni Bressan Stefano Kravanja Gianlorenzo Franceschina 《Physics of the Earth and Planetary Interiors》2007,160(3-4):192-214
The source parameters of the major events of a swarm and of two seismic sequences, occurred in the Friuli area (Northeastern Italy) and in Western Slovenia, were estimated. The Claut swarm (C96) occurred since the end of January to June 1996, with a MD 4.3 major shock and it appears composed of three sub-sequences. The two sequences are the Kobarid sequence (K98) started on April 12, 1998 with a MD 5.6 mainshock and the M.te Sernio (S02) sequence caused by the February 14, 2002 earthquake (MD = 4.9). Acceleration and velocity data recorded by the local seismic network of the Istituto Nazionale di Oceanografia e di Geofisica Sperimenale (OGS) and corrected for attenuation, were employed to estimate seismic moments and radiated energies. Source dimensions were inferred from the computed corner frequencies and the stress release was estimated from the Brune stress drop, the apparent stress and the RMS stress drop. On the whole, seismic moments range from 1.7 × 1012 to 1.1 × 1017 N m, and radiated energies are in the range 106–1013 J. Brune stress drops are scattered and do not show any evidence of a self-similarity breakdown for sources down to 130 m radius. The radiated seismic energy scales as a function of seismic moment, with a slope of the scaling relation that decreases for increasing seismic moments.The mechanism of stress release was analyzed by computing the ɛ parameter of Zuniga [Zuniga, R., 1993. Frictional overshoot and partial stress drop. Which one? Bull. Seismol. Soc. Am. 83, 939–944]. The K98 and S02 sequences are characterized by a wide range of the ɛ parameter with stress drop mechanism varying from partial locking to overshoot cases. The ɛ values of the C96 swarm are more homogeneous and close to the Orowan's condition. The radiated seismic energy and the ratio of stress drop between mainshock and aftershocks appear different among the analyzed cases. We therefore investigated the relationship between the stress parameters of the main shock and the energy radiated by the aftershock sequences. For this purpose, we also estimated the source parameters of two other sequences occurred in the area, with mainshocks of MD 4.1 and 5.1, respectively. We found a positive correlation between the Brune stress drop of the mainshock and the ratio between the radiated energy of the mainshock and the summation of the energies radiated by the aftershocks. 相似文献
15.
In this study, strong ground motion record(SGMR) selection based on Eta(η) as a spectral shape indicator has been investigated as applied to steel braced frame structures. A probabilistic seismic hazard disaggregation analysis for the definition of the target Epsilon(ε) and the target Eta(η) values at different hazard levels is presented, taking into account appropriately selected SGMR's. Fragility curves are developed for different limit states corresponding to three representative models of typical steel braced frames having significant irregularities in plan, by means of a weighted damage index. The results show that spectral shape indicators have an important effect on the predicted median structural capacities, and also that the parameter η is a more robust predictor of damage than searching for records with appropriate ε values. 相似文献
16.
The paper presents the results of a joint analysis of ground-based and satellite observations of very low-frequency and low-frequency (VLF/LF) signals during periods of strong seismic activity in the region of Kuril Islands and Japan in 2004–2010. Ground and satellite data was processed using a method based on the difference between the real signal in nighttime and that of a model. The results of the analysis show a good correlation between ground-based and satellite data for several cases of strong (M ⩾ 6.8) earthquakes. 相似文献
17.
Universality of the Seismic Moment-frequency Relation 总被引：1，自引：0，他引：1
Y. Y. Kagan 《Pure and Applied Geophysics》1999,155(2-4):537-573
—We analyze the seismic moment-frequency relation in various depth ranges and for different seismic regions, using Flinn-Engdahl's regionalization of global seismicity. Three earthquake lists of centroid-moment tensor data have been used the Harvard catalog, the USGS catalog, and the Huang et al. (1997) catalog of deep earthquakes. The results confirm the universality of the β-values and the maximum moment for shallow earthquakes in continental regions, as well as at and near continental boundaries. Moreover, we show that although fluctuations in earthquake size distribution increase with depth, the β-values for earthquakes in the depth range of 0–500 km exhibit no statistically significant regional variations. The regional variations are significant only for deep events near the 660 km boundary. For declustered shallow earthquake catalogs and deeper events, we show that the worldwide β-values have the same value of 0.60 ± 0.02. This finding suggests that the β-value is a universal constant. We investigate the statistical correlations between the numbers of seismic events in different depth ranges and the correlation of the tectonic deformation rate and seismic activity (the number of earthquakes above a certain threshold level per year). The high level of these correlations suggests that seismic activity indicates tectonic deformation rate in subduction zones. Combined with the universality of the β-value, this finding implies little if any variation in maximum earthquake seismic moment among various subduction zones. If we assume that earthquakes of maximum size are similar in different depth ranges and the seismic efficiency coefficient, χ, is close to 100% for shallow seismicity, then we can estimate χ for deeper earthquakes for intermediate earthquakes χ≈ 5%, and χ≈ 1% for deep events. These results may lead to new theoretical understanding of the earthquake process and better estimates of seismic hazard. 相似文献
18.
A. V. Novopashina V. A. San’kov V. Yu. Buddo 《Journal of Volcanology and Seismology》2012,6(4):259-267
The epicenter field of earthquakes that occur in the Baikal Rift System (BRS) was analyzed to identify certain areas that have stable concentrations of seismic events; these are reflections (in time) of deformable earthquake-generating volumes in the tectonosphere, or earthquake-generating structures. The patterns that are identifiable in the interrelationships and interactions of earthquake-generating structures as found by analysis of the space-time characteristics of the seismic process characterize the present-day dynamics of the BRS. Time series of earthquake-generating structures were analyzed for the 1964?C2002 period using the following parameters: the number of earthquakes (N) and the logarithm of total energy released by the earthquakes (log Esum). The tool was frequency-time analysis (FTAN), which revealed dominant periodic components in the seismic process for each earthquake-generating structure. We also used correlation analysis based on the parameter N to determine the order of activation for the earthquake-generating structures and to identify periods of synchronization in the seismic process. 相似文献
19.
J. Perez-Oregon A. Muñoz-Diosdado A. H. Rudolf-Navarro A. Guzmán-Sáenz F. Angulo-Brown 《Journal of Seismology》2018,22(4):1025-1035
The study of the Gutenberg-Richter (GR) parameters a and b has been very important to describe and characterize the seismicity over the different seismic provinces around the world. As far as we know, the possible correlation between the GR parameters a and b has not received enough attention. Bayrak et al. reported the a and b values for 27 active seismic regions around the boundaries of the main tectonic plates of the world. From these data, we found that there exists a positive correlation between the a and b parameters (R =?0.85, R2 =?0.72). On the other hand, we made around 150 computer runs of a spring-block model proposed by Olami et al. (Phys Rev Lett 68(8):1244–1247, 1992). This model roughly emulates the interaction between two fault planes and it reaches a self-organized critical state. With these simulations, we also found that the a and b parameters are positively correlated. Motivated by these results, we propose an analytical demonstration that indeed a and b are positively correlated. In addition, we discuss on other possible applications of the spring-block model to actual seismicity and to frictional experiments made with sandpapers. 相似文献
20.
背景噪声层析成像技术已被广泛应用于地壳和上地幔速度结构的研究,这种方法不依靠地震的发生和人工源爆破,只需记录连续的噪声信号而无需产生信号,因为噪声穿过地下介质时会携带信息,然后通过利用台站记录到的连续背景噪声数据进行互相关计算和叠加,即可得到台站间的经验格林函数,从而获取对地下结构的认识。这种方法已经很好地应用于中国的东北地区、华北克拉通、青藏高原以及华南地区,并成功地揭示了这些地区地壳与上地幔顶部的速度结构。此外近年来,一些学者还利用噪声互相关技术研究地下介质地震波速度随时间的变化,通过对汶川大地震前后连续噪声记录的研究发现,大震发生后呈现同震波速降低和震后波速逐渐恢复的特点,这表明可以通过观测地震波特性的变化来监测地下应力的变化,从而为大震的预测预防工作提供科学依据。本文主要综述了近些年来背景噪声技术及其在中国大陆地区的应用。 相似文献