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1.
AsourceextentanalysisoftheLancangearthquake(Ms=7.6)of1988SI-HUAZHENG(郑斯华)JIANYANG(杨健)CenterforAnalysisandprediction,ChinaSeis...  相似文献   

2.
Expertsystemforearthquakeprediction(ESEP)(2)-KnowledgerepresentationandevidencecombinationHong-ShunFAN(范洪顺)andBi-QuanWANG(王碧泉...  相似文献   

3.
Studyonthesourcesofsomedeepfocusearth┐quakesinNorthwestPacificregionAN-YILI(李安奕)andSHAO-XIANZANG(臧绍先)GeophysicsDepartment,Pe...  相似文献   

4.
《ActaSeismologicaSinica》isinprogress──reporttothefourthsessionofacademicsymposlumofSSContheworkofASS(1992-1994)Xin-MeiLIUandY...  相似文献   

5.
Thefracturecharacteristicofthe1989Datong-YanggaoearthquakesequenceSi-ChangZHANG(张四昌),Gui-LingDIAO(刁桂苓)andLi-MinYU(于利民)(Sefrmo...  相似文献   

6.
StochasticmodelofbedrockearthquakemotionanddeterminationofitsparametersDi-TaoNIU(牛荻涛)(Xi'anUniversityofArchitecturalSciencean...  相似文献   

7.
ThestudyandapplicationofPTRalgorithmonrecognizingvariousstructuresamplesBi-QuanWANG(王碧泉);Han-MingHUANG(黄汉明)andHong-ShunFAN(范洪...  相似文献   

8.
BinomialmodelonseismicriskanalysisJianWANG(王健)andZhen-LiangSHI(时振梁)(InstituteofGeophysics,StateSeismologicalBureau,Beijing100...  相似文献   

9.
ResearchonnonlinearR/SmethodanditspplicationinearthquakepredictionBi-QuanWANG(王碧泉);Han-MingHUANG(黄汉明);Hong-ShunFAN(范洪顺);Chuen...  相似文献   

10.
Strongstrong-moderateearthquakeactivity withinandnearChina(September-November,1995)PEI-SHANCHEN(陈培善)(InstistuteofGeophysics,S...  相似文献   

11.
姜慧  杨章  唐丽华  马巍 《内陆地震》2000,14(3):228-233
为满足水库抗震设计的震要,合成了50年超越概率5%和100年超越概率2%的基岩加速度时程曲线,考虑到吉林吉台电站所处的特殊地震环境和场地条件,分析其地震危险性认为:50年超越概率5%的地震动为远震影响;100年超越概率2%的地震动为近震影响,目前使用的基岩加带度反应谱衰关于关系的来源资料多少丢失一些高频成分,可能低估高频成分的地震动对基岩场地的影响,为此根据大震,远震的特征周期Tg较大这一规律,把两个概率水平的加速度反应谱的特征周期Tg都定为0.3s,并增加基岩反应谱高频成分控制,从而把基岩地震加速度反应谱处理成相应的规准谱,在此基础上通过拟合规准谱合成的基岩地震动时程曲线,较好地满足坝址的设防要求。  相似文献   

12.
-- We investigate the impact of different rupture and attenuation models for the Cascadia subduction zone by simulating seismic hazard models for the Pacific Northwest of the U.S. at 2% probability of exceedance in 50 years. We calculate the sensitivity of hazard (probabilistic ground motions) to the source parameters and the attenuation relations for both intraslab and interface earthquakes and present these in the framework of the standard USGS hazard model that includes crustal earthquakes. Our results indicate that allowing the deep intraslab earthquakes to occur anywhere along the subduction zone increases the peak ground acceleration hazard near Portland, Oregon by about 20%. Alternative attenuation relations for deep earthquakes can result in ground motions that differ by a factor of two. The hazard uncertainty for the plate interface and intraslab earthquakes is analyzed through a Monte-Carlo logic tree approach and indicates a seismic hazard exceeding 1 g (0.2 s spectral acceleration) consistent with the U.S. National Seismic Hazard Maps in western Washington, Oregon, and California and an overall coefficient of variation that ranges from 0.1 to 0.4. Sensitivity studies indicate that the paleoseismic chronology and the magnitude of great plate interface earthquakes contribute significantly to the hazard uncertainty estimates for this region. Paleoseismic data indicate that the mean earthquake recurrence interval for great earthquakes is about 500 years and that it has been 300 years since the last great earthquake. We calculate the probability of such a great earthquake along the Cascadia plate interface to be about 14% when considering a time-dependent model and about 10% when considering a time-independent Poisson model during the next 50-year interval.  相似文献   

13.
The sensitivity and overall uncertainty in peak ground acceleration (PGA)estimates have been calculated for the city of Tabriz, northwestern Iran byusing a specific randomized blocks design. Eight seismic hazard models andparameters with randomly selected uncertainties at two levels have beenconsidered and then a linear model between predicted PGA at a givenprobability level and the uncertainties has been performed. The inputmodels and parameters are those related to the attenuation, magnituderupture-length and recurrence relationships with their uncertainties.Application of this procedure to the studied area indicates that effects ofthe simultaneous variation of all eight input models and parameters on thesensitivity of the seismic hazard can be investigated with a decreasingnumber of computations for all possible combinations at a fixed annualprobability. The results show that the choice of a mathematical model ofthe source mechanism, attenuation relationships and the definition ofseismic parameters are most critical in estimating the sensitivity of seismichazard evaluation, in particular at low levels of probability of exceedance.The overall uncertainty in the expected PGA for an annual probability of0.0021 (10% exceedence in 50 yr) is expressed by a coefficient ofvariation (CV) of about 34% at 68% confidence level for a distance ofabout 5km from the field of the major faults. The CV will decrease withincreasing site-source distance and remains constant, CV = 15%, fordistances larger than 15 km. Finally, treating alternative models on theoverall uncertainty are investigated by additional outliers in input decision.  相似文献   

14.
地震危险性概率分析(PSHA)是目前最广泛应用于地震灾害与风险性评估的方法。然而它在计算中却存在着一个错误:把强地面运动衰减关系(一个函数)的条件超越概率等同于强地面运动误差(一个变量)的超越概率。这个错误导致了运用强地面运动误差(空间分布特征)去外推强地面运动的发生(时间分布特征)或称之为遍历性假设,同时也造成了对PSHA理解和应用上的困难。本文推导出新的灾害计算方法(称之为KY-PSHA)来纠正这种错误。  相似文献   

15.
IntroductionTodetermineaseismicdesignstandard,examineaseismicdesignorpredictseismicdamage,theparametersofgroundmotioneventim...  相似文献   

16.
For Probabilistic Tsunami Hazard Analysis (PTHA), we propose a logic-tree approach to construct tsunami hazard curves (relationship between tsunami height and probability of exceedance) and present some examples for Japan for the purpose of quantitative assessments of tsunami risk for important coastal facilities. A hazard curve is obtained by integration over the aleatory uncertainties, and numerous hazard curves are obtained for different branches of logic-tree representing epistemic uncertainty. A PTHA consists of a tsunami source model and coastal tsunami height estimation. We developed the logic-tree models for local tsunami sources around Japan and for distant tsunami sources along the South American subduction zones. Logic-trees were made for tsunami source zones, size and frequency of tsunamigenic earthquakes, fault models, and standard error of estimated tsunami heights. Numerical simulation rather than empirical relation was used for estimating the median tsunami heights. Weights of discrete branches that represent alternative hypotheses and interpretations were determined by the questionnaire survey for tsunami and earthquake experts, whereas those representing the error of estimated value were determined on the basis of historical data. Examples of tsunami hazard curves were illustrated for the coastal sites, and uncertainty in the tsunami hazard was displayed by 5-, 16-, 50-, 84- and 95-percentile and mean hazard curves.  相似文献   

17.
本文采用了空间光滑地震活动性模型,该模型无需潜在震源区划分,同时发展了概率地震危险性分析新方法。根据三种地震目录资料建立了三种地震活动性模型,利用高斯光滑函数获得了湖南区域内的比值分布特征,使用了两种典型的衰减模型,计算了50年内超越概率10%的地震动峰值加速度(PGA)分布。其分析结果显示PGA分布特征与中国地震动参数区划图大体一致,部分区域PGA提高,PGA达0.05g的区域显著扩大,其中包括邵阳、湘潭、吉首、怀化等重要城市,而这种PGA分布特征与该地区地震活动性特征是一致的。概率危险性曲线的结果表明常德等地区的潜在地震危险性比湖南区域内其他城市高。表明此模型用于地震危险性计算中是简便易行的,且具有较高的精度。尤其对于地质和地震构造信息缺乏的弱震区和中强震区,该方法作为替代方法并有着广泛的应用价值。  相似文献   

18.
论工程抗震设防标准   总被引:40,自引:12,他引:40  
本文论述了工程抗震设防标准在防震减灾工作中的重要作用和地位,总结分析了工程抗震设防标准工作的发展、现状和存在的问题,探讨了工程抗震设防标准工作的涵意和内容,作者认为工程设防标准工作应包括确定合理的设防原则,适当的设防目标,科学的设防环境(地震)、便于应用的设防参数,与社会经济条件相符合的设防水准和设防等级,文中并对设防水准与等级的表述方式提出了具体的建议。从而为制定工程抗震设防标准工作建立起一个科  相似文献   

19.
论工程抗震设防标准   总被引:16,自引:0,他引:16  
本文论述了工程抗震设防标准在防震减灾工作中的重要作用和地位,总结分析了工程抗震设防标准工作的发展,现状和存在的问题,探讨了工程抗震设防标准工作的涵意和内容。作者认为设防标准工作应包括确定合理的设防原则,适当的设防目标,科学的设防环境,便于应用的设防参数,与社会经济条件相符合的设防水准和设防等级。  相似文献   

20.
基于单一指标的传统地震易损性分析忽略了非结构构件损伤对建筑抗震性能的影响。首先基于多维性能极限状态理论建立了三维性能极限状态方程,并对几种特殊情况下的三维阈值曲面进行了讨论。进而以最大层间位移角作为整体结构与位移敏感型非结构构件的性能指标,以峰值楼面加速度作为加速度敏感型非结构构件的性能指标,对建筑的结构损伤和非结构损伤进行描述。考虑各性能指标之间的相关性和各性能指标所对应的极限状态阈值的不确定性,建立了建筑在地震作用下的三维性能极限状态的超越概率函数。最后,采用Open Sees有限元软件对一7层钢筋混凝土框架填充墙建筑进行增量动力分析,得到其各性能水平下的地震易损性曲线。分析结果表明,当忽略非结构构件损伤时,各性能极限状态的超越概率均降低,从而高估了建筑剩余功能水平,进而导致低估建筑的损失。在考虑各性能指标的极限状态阈值的不确定性时,对任一性能极限状态,不同变异系数取值下的易损性曲线会出现交点,在交点之前超越概率随着变异系数的增大而增大,交点之后则随着变异系数的增大而减小。在考虑性能指标间的相关性时,对任一性能极限状态,超越概率随着相关系数的减小而增大。另外,性能指标阈值的不确定性与性能指标间的相关性对地震易损性的影响随着性能水平的提高而逐渐降低,且对低性能水平下建筑地震易损性有明显影响。  相似文献   

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