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1.
Introduction The estimation of damage probability distribution among different damage states of rein-forced concrete buildings is a key component of earthquake loss estimation for modern city or a group of cities. With the development of city, the reinforced concrete buildings are major compo-nent parts of modern cities. Vulnerability estimates for these kinds of buildings are of importance to those responsible for civil protection, relief, and emergency services to enable adequate contin-genc… 相似文献
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3.
Robin K. McGuire 《地震工程与结构动力学》1977,5(3):211-234
The calculation of design spectra for building sites threatened by seismic ground motion is approached by considering the maximum responses of linearly elastic oscillators as indicators of ground motion intensity. Attenuation functions describing the distribution of response as a function of earthquake magnitude and distance are derived using 68 components of recorded ground motion as data. With a seismic hazard analysis for several hypothetical building sites, the distributions of maximum oscillator responses to earthquakes of random magnitude and location are calculated, and spectra are drawn to indicate the maximum responses associated with specified probability levels. These spectra are compared to design spectra calculated from published methods of amplifying peak ground motion parameters. The latter spectra are found to be inconsistent in terms of risk for building sites very close and very far from faults. A ground motion parameter defined to be proportional to the maximum response of a 1 Hz, 2 per cent damped linearly elastic oscillator is investigated; this parameter, in conjunction with peak ground acceleration, is found to lead to risk-consistent design spectra. Through these two parameters, a design earthquake magnitude and design hypocentral distance are defined, for a specified building site and risk level. The use of these parameters in the seismic hazard mapping of a region is illustrated. 相似文献
4.
Kamal Abdel-Rahman El-Sayed 《地震研究》2008,31(2):160-170
根据埃及Gasco天然气公司工程场地的现场调查资料、地震活动性和地震灾害评估结果,对该场地进行了评估.通过浅源地震波折射勘探,对8个地震剖面上的土壤和岩石的弹性动态常数进行了分析.场地地面模型包括两层,分析表明它们具有从中值到高值的弹性动态常数,说明场地有良好的土壤条件和基岩岩性.同时,我们搜集和分析了研究区周围150 km半径范围内的历史和仪器记录地震,从构造环境、地震活动性、地质构造和主要地震的断层面解等方面进行了研究,认为场地受4个震源区的影响:苏伊士中部海湾、开罗-苏伊士地区、开罗西南和Beni-Suef地区.我们采用地震活动性统计方法并结合专家判定,确定了这些震源区内最大地震的矩震级(MW).另外,依据场地峰值加速度(PGA)和反应谱,用随机方法对场地进行了地震灾害评估.4个震源区中,Beni-Suef地区距离工程场地最近,其PGA最大值为9.34cm/s2,但这个值很小,表明地震不会对工程场地产生破坏性影响.最后,我们还模拟了阻尼为1%、3%和5%时的伪加速度场地反应谱. 相似文献
5.
A representative attenuation relationship is one of the key components required in seismic hazard assessment of a region of interest. Attenuation relationships for peak ground acceleration, peak ground velocity and response spectral accelerations for Sumatran megathrust earthquakes, covering Mw up to 9.0, are derived based on synthetic seismograms obtained from a finite‐fault kinematic model. The relationships derived are for very hard rock site condition and for a long‐distance range between 200 and 1500 km. They are then validated with recorded data from giant earthquakes on the Sumatran megathrust occurring since year 2000. A close examination of the recorded data also shows that spectral shapes predicted by most of the existing attenuation relationships and that specified in the IBC code are not particularly suitable for sites where potential seismic hazard is dominated by large‐magnitude, distant, earthquakes. Ground motions at a remote site are typically signified by the dominance of long‐period components with periods longer than 1 s, whereas the predominant periods from most of the existing attenuation relationships and the IBC code are shorter than 0.6 s. The shifting of response spectrum towards longer period range for distant earthquakes should be carefully taken into account in the formulation of future seismic codes for Southeast Asia, where many metropolises are located far from active seismic sources. The attenuation relationship derived in the present study can properly reproduce the spectral shape from distant subduction earthquakes, and could hopefully give insights into the formulation of future seismic codes. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
6.
A physics‐based numerical approach is used to characterize earthquake ground motion due to induced seismicity in the Groningen gas field and to improve empirical ground motion models for seismic hazard and risk assessment. To this end, a large‐scale (20 km × 20 km) heterogeneous 3D seismic wave propagation model for the Groningen area is constructed, based on the significant bulk of available geological, geophysical, geotechnical, and seismological data. Results of physics‐based numerical simulations are validated against the ground motion recordings of the January 8, 2018, ML 3.4 Zeerijp earthquake. Taking advantage of suitable models of slip time functions at the seismic source and of the detailed geophysical model, the numerical simulations are found to reproduce accurately the observed features of ground motions at epicentral distances less than 10 km, in a broad frequency range, up to about 8 Hz. A sensitivity analysis is also addressed to discuss the impact of 3D underground geological features, the stochastic variability of seismic velocities and the frequency dependence of the quality factor. Amongst others, results point out some key features related to 3D seismic wave propagation, such as the magnitude and distance dependence of site amplification functions, that may be relevant to the improvement of the empirical models for earthquake ground motion prediction. 相似文献
7.
目前我国针对陆域地区的建筑物和构筑物已建立了比较完备的抗震设计理论和技术体系,但对于海洋工程的抗震研究工作开展得不充分,尤其是海洋岛礁场地的地震反应分析尚属空白。伴随着近年来我国南海地区的迅速开发建设,有必要对南海岛礁的地震危险性分析和抗震设计展开研究。介绍南海岛礁场地的特殊工程地质条件和地震活动性特征,通过比较目前国内外常用的场地地震反应分析方法,针对岛礁这一特殊工程地质体,提出岛礁场地地震反应分析中需要考虑的四个显著因素,包括(1)南海岛礁体的特殊地形;(2)南海岛礁特殊的岩土工程材料;(3)海水-岛礁体动力相互作用;(4)南海地区海底输入地震动的确定,并探讨解决这些问题的思路。为分析地震作用下岛礁场地的稳定性、场地反应分析提供研究思路,同时为南海岛礁建设中的地震危险性分析提供参考。 相似文献
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高孟潭 《地震学报(英文版)》1994,7(3):441-446
ＥｘｐｅｃｔｅｄｍａｇｎｉｔｕｄｅａｎｄｄｉｓｔａｎｃｅｏｆｐｏｔｅｎｔｉａｌｓｏｕｒｃｅａｒｅａａｎｄｔｈｅｅｓｔｉｍａｔｉｎｇｍｅｔｈｏｄＭｅｎｇ－ＴｔａｎＧＡＯ（高孟潭）（ＩｎｓｔｉｔｕｔｅｏｆＧｅｏｐｈｙｓｉｃｓ，ＳｔａｔｅＳｅｉｓｍｏｌｏｇ... 相似文献
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Selection and ranking of ground motion models for seismic hazard analysis in the Pyrenees 总被引：1，自引：0，他引：1
Stéphane Drouet Frank Scherbaum Fabrice Cotton Annie Souriau 《Journal of Seismology》2007,11(1):87-100
The issue addressed in this paper is the objective selection of appropriate ground motion models for seismic hazard assessment
in the Pyrenees. The method of Scherbaum et al. (2004a) is applied in order to rank eight published ground motion models relevant to intraplate or to low deformation rate contexts.
This method is based on a transparent and data-driven process which quantifies the model fit and also measures how well the
underlying model assumptions are met. The method is applied to 15 accelerometric records obtained in the Pyrenees for events
of local magnitude between 4.8 and 5.1, corresponding to moment magnitudes ranging from 3.7 to 3.9. Only stations at rock
sites are considered. A total of 720 spectral amplitudes are used to rank the selected ground motion models. Some control
parameters of these models, such as magnitude and distance definitions, may vary from one model to the other. It is thus important
to correct the selected models for their difference with respect to the magnitude and distance definitions used for the Pyrenean
data. Our analysis shows that, with these corrections, some of the ground motion models successfully fit the data. These are
the Lussou et al. (2001) and the Berge-Thierry et al. (2003) models. According to the selected ground motion models, a possible scenario of a magnitude 6 event is proposed; it predicts
response spectra accelerations of 0.08–0.1 g at 1 Hz at a hypocentral distance of 10 km. 相似文献
10.
工程结构等延性地震抗力谱研究 总被引：28，自引：7，他引：21
研究结构的非弹性反应谱对改进现有的结构抗震设计、发展基于性态的抗震设计以及了解复杂地面运动特性与结构动力特性之间的关系具有重要的意义。利用大量的单自由度在强震记录作用下的弹塑性动力时程分析,对等延性地震抗力谱这一重要的非弹性反应谱进行了较为详尽的研究,给出了四类场地条件(基岩、硬土、一般土和软土)下的平均等延性地震抗力谱,总结了对工程结构的抗震设计和研究具有实际意义的规律和特征,并分析了场地条件、结构的延性系数以及周期等对等延性地震抗力谱的影响,提出了新的拟合公式,其成果可供抗震研究和设计直接应用。 相似文献
11.
Brendon A. Bradley Rajesh P. Dhakal Gregory A. MacRae Misko Cubrinovski 《地震工程与结构动力学》2010,39(5):501-520
The efficacy of various ground motion intensity measures (IMs) in the prediction of spatially distributed seismic demands (engineering demand parameters, (EDPs)) within a structure is investigated. This has direct implications to building‐specific seismic loss estimation, where the seismic demand on different components is dependent on the location of the component in the structure. Several common IMs are investigated in terms of their ability to predict the spatially distributed demands in a 10‐storey office building, which is measured in terms of maximum interstorey drift ratios and maximum floor accelerations. It is found that the ability of an IM to efficiently predict a specific EDP depends on the similarity between the frequency range of the ground motion that controls the IM and that of the EDP. An IMs predictability has a direct effect on the median response demands for ground motions scaled to a specified probability of exceedance from a ground motion hazard curve. All of the IMs investigated were found to be insufficient with respect to at least one of magnitude, source‐to‐site distance, or epsilon when predicting all peak interstorey drifts and peak floor accelerations in a 10‐storey reinforced concrete frame structure. Careful ground motion selection and/or seismic demand modification is therefore required to predict such a spatially distributed demands without significant bias. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
12.
An integrated probabilistic seismic hazard analysis procedure that incorporates nonlinear site effects, PSHA-NL, is developed and used to characterize the influence of thick deposits of the upper Mississippi Embayment (ME) on seismic site coefficients. PSHA-NL follows the methodology of the 2002 USGS hazard maps and generates a compatible set of ground motion records. The motions are propagated using nonlinear and equivalent linear site response analyses and ME properties developed in a companion paper and used to derive surface uniform hazard response spectra. A set of generic site coefficients are derived and summarized in a format similar to NEHRP site coefficients, with an added dimension of ME deposits thickness to the Paleozoic rock, a physically meaningful impedance boundary. These coefficients compare well with NEHRP site coefficients for 30 m profiles. For thicker soil profiles, developed site coefficients are lower at short periods and higher at long periods than NEHRP site coefficients. 相似文献
13.
Local site conditions can significantly influence the characteristics of seismic ground motions. In this study, site response analyses using one-dimensional linear elastic (LE), equivalent-linear (EQL) and nonlinear (NL) approaches are performed at different seismic hazard levels of Singapore. Two seismic stations, namely, the KAP and BES stations located at soft soil sites, are selected from the national network of Singapore. Firstly, site response estimates using the LE, EQL (SHAKE04) and NL (DEEPSOIL) approaches are compared with the borehole recordings. Results show favorable matches between the predictions and the observations at the KAP site, while under-predictions are observed for all the three site effect approaches at the BES site. Secondly, the applicability of the LE, EQL and NL models is examined at different hazard levels of Singapore. It is found that for the hazard level at a return period of 475 years, the computed maximum strain (γmax) is 0.06% and then the EQL model can provide accurate site response predictions. However, for the hazard level at a return period of 2475 years, the calculated γmax is larger than 2%, resulting in notable differences in the predictions of different site response models. This study highlights the importance of site effects in seismic hazard analysis of Singapore. 相似文献
14.
Tsuneo Katayama 《地震工程与结构动力学》1982,10(1):149-163
A regression analysis was made on 277 acceleration response spectra computed from Japanese accelerograms by subdividing the data into discrete categories. Five magnitude and distance categories, and four ground condition categories were used. The maximum absolute acceleration amplitude is predicted as a product of three factors, each representing a weighting factor for magnitude, distance and ground condition category at each of the 18 response spectrum periods from 0·1 s to 4 s at a damping value of 5 per cent of critical. A method was then developed to evaluate seismic hazard in terms of acceleration response spectrum by using the prediction model and the seismicity data, and it was applied to obtain seismic macro-zoning maps of Japan which are dependent on the natural period of a structure. The results of the analysis indicated that a single seismic zoning map may not be sufficient to cover a variety of structures with a wide range of periods because the expected spectral shape differs according to the seismicity of the area. 相似文献
15.
L. Peruzza A. Rebez D. Slejko P. L. Bragato 《Soil Dynamics and Earthquake Engineering》2000,20(5-8):361-371
Probabilistic seismic hazard maps, in terms of spectral acceleration and uniform hazard response spectra at given sites, considering local soil conditions, represent a much more complete estimate of the seismic hazard than the traditional maps in terms of peak ground acceleration or macroseismic intensity. This is particularly true when the requests of urban planners and engineers have to be met. The present analysis shows how some hazard parameters, such as the effective peak acceleration and the spectrum intensity, can well synthesise the overall information available from traditional probabilistic studies, but also suggests that soil condition is a first-order ingredient for effective seismic hazard mapping at national level. Three Italian towns, damaged by the 1997 Umbria–Marche earthquake sequence, are considered as example to demonstrate that: (1) soil condition dependent uniform hazard spectra well approximate actual spectra recorded during some events of the seismic sequence; (2) for these localities, the design spectrum of the present Italian seismic code does not seem adequate.
These considerations have induced the Italian scientific community to propose an updating of the national seismic zonation on the basis of several hazard parameters, that are described in this paper. 相似文献
16.
In performance-based seismic design, as adopted by several building codes worldwide, the structural performance is verified against ground motions that have predetermined exceedance return periods at the site of interest. Such a return period is evaluated by means of probabilistic seismic hazard analysis (PSHA), and the corresponding ground motion is often represented by the uniform hazard spectrum (UHS). The structural performance for ground motions larger than those considered in this design approach is, typically, not explicitly controlled under the assumption that they are sufficiently rare. On one hand, this does not achieve uniform safety at sites characterized by different design ground motions corresponding to the same return period; on the other hand, exceedances of the design spectra are systematically observed over large areas, for example in Italy. The latter issue is because of the nature of UHS, the exceedance of which is likely-to-almost-certain when the construction site is in the epicentral area of moderate-to-high magnitude earthquakes (ie, the design spectrum may be not conservative at these locations), especially if PSHA is based on seismic source zones. The former is partially because of the systematic difference of ground motions for return periods larger than the design one at the different sites. Quantification of the expected ground motion given the exceedance of the design ground motions (ie, the recently introduced as the expected peak-over-threshold or POT) can be of help in quantitatively assessing these issues. In the study, a procedure to compute the POT distribution is derived first; second, POT spectra are introduced and used to help understanding why and how seismic structural reliability of code-conforming structures decreases as the seismic hazard of the site increases; third, expected and 95th percentile POT maps are shown for Italy to discuss how much high hazard sites are exposed to much larger peak-over-threshold with respect to mid-hazard and low-hazard sites; finally the POT is discussed with respect to the slope of the hazard curve (in log-log scale) at the threshold, a known proxy for ground motion beyond design. All data presented in the maps are made available for the interested reader as a supplemental archive. 相似文献
17.
DISCUSSION ON THE SPECTRA SHAPE OF SEISMIC MARGIN EARTHQUAKE OF NUCLEAR POWER PLANT IN CHINA 
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下载免费PDF全文 Fukushima nuclear accident caused widespread concern of earthquake initiated severe accident. Under this background, China nuclear utilities carried out research and application of seismic margin assessment(SMA)approach to evaluate the seismic margin of the existing nuclear power plants(NPP)by different spectra shape of seismic margin earthquake(SME). By reviewing the method used to determine SME of operational NPP in central and eastern United States(CEUS), this paper analyzed the seismic hazard characteristic of China NPP sites, contrasted the design basis ground motion between NPP in CEUS and China, and suggested giving priority to evaluating the seismic margin of operational NPP that adopted the improved second generation technology for the urgency and importance of assessment on the actual seismic capacity of NPP. Comparing RG1.60 spectrum to normalized site-specific SL-2 level acceleration spectra, we found that some normalized spectra overtook the RG1.60's in high frequency range, so it is not always adequate to scale RG1.60 spectrum to evaluate the seismic margin for sites of the improved second generation NPP. We selected a sample site whose site-specific SL-2 level ground motion is close to the standard design of improved second generation NPP(0.2g scaled RG1.60 spectrum)to determine the seismic margin earthquake by probabilistic seismic hazard analysis method of the sample site. Compared to the given PGA(0.3g)scaled scenario earthquake ground motions and the uniform hazard response spectrum(UHRS), whose PGA is 0.3g to PGA(0.3g)scaled standard spectra(median NUREG/CR0098 spectrum and RG1.60 spectrum), the results demonstrated that uniform hazard response spectrum and scaled scenario earthquake ground motions are both significantly higher than the PGA scaled median NUREG/CR0098 spectrum, and all the three spectra are enveloped by PGA scaled RG1.60 spectrum. Then, this paper suggests adopting the uniform hazard response spectrum or scenario earthquake ground motions to evaluate the seismic margin of improved second generation NPP beyond site SL-2 ground motion; and to evaluate the seismic margin of improved second generation NPP beyond standard design, we recommend to use PGA scaled RG1.60 spectrum. 相似文献
18.
H. Parra M. B. Benito J. M. Gaspar-Escribano 《Bulletin of Earthquake Engineering》2016,14(8):2129-2159
A seismic hazard assessment study of continental Ecuador is presented in this paper. The study begins with a revision of the available information on seismic events and the elaboration of a seismic catalog homogenized to magnitude Mw. Different seismic source definitions are revised and a new area-source model, based on geological and seismic data, is proposed. The available ground motion prediction equations for crustal and subduction sources are analyzed and selected for the tectonic environments observed in Ecuador. A probabilistic seismic hazard assessment approach is carried out to evaluate the exceedance probability of several levels of peak ground acceleration PGA and spectral accelerations SA (T) for periods (T) of 0.1, 0.2, 0.5, 1 and 2s. The resulting hazard maps for continental Ecuador are presented, together with the uniform hazard spectra of four province capital cities. Hazard disaggregation is carried out for target motions defined by the PGA values and SA (1s) expected for return periods of 475 and 2475 years, providing estimates for short-period and long-period controlling earthquakes. 相似文献
19.
本文根据保定市及周围地区的地震地质环境，在地震危险性分析的基础上，采用等效线性一维波动方程进行土层的地震反应分析。给出50年超越概率63％、10％、2％基岩和地面的水平向峰值加速度、反应谱（场址基本烈度Ⅶ度）和地震影响系数最大值。该结果为抗震设计提供了可靠依据，具有应用价值。 相似文献
20.
Safety against earthquake hazards presents two aspects: structural safety against potentially destructive dynamic forces and site safety related to geotechnical phenomena, such as amplification, landsliding and soil liquefaction. The correct evaluation of seismic hazard is, therefore, highly affected by risk factors due to geological nature and geotechnical properties of soils. In response to these new developments, several attempts have been made to identify and appraise geotechnical hazards and to represent them in the form of zoning maps, in which locations or zones with different levels of hazard potential are identified. The geotechnical zonation of the subsoil of the city of Catania (Italy) suggests a high vulnerability of the physical environment added to site amplification of the ground motion phenomena. The ground response analysis at the surface, in terms of time history and response spectra, has been obtained by some 1D equivalent linear models and by a 2D linear model, using a design scenario earthquake as input at the conventional bedrock. In particular, the study has regarded the evaluation of site effects in correspondence of the database of about 1200 boreholes and water-wells available in the data-bank of the Catania area. According to the response spectra obtained through the application of the 1D and 2D models, the city of Catania has been divided into some zones with different peak ground acceleration at the surface, to which corresponds a different value of the Seismic Geotechnical Hazard. A seismic microzoning map of the urban area of the city of Catania has been obtained. The map represents an important tool for the seismic improvement of the buildings, indispensable for the mitigation of the seismic risk. 相似文献