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1.
《地震》2017,(3)
在收集和整理内蒙古及邻近地区1940年以来M_S4.0以上历史震害资料的基础上,对研究区域进行合理分区,选取65次中强地震事件的152条等震线数据,利用椭圆烈度衰减模型,采用Levenberg-Marquardt非线性反演方法,建立内蒙古及邻区的分区地震烈度衰减关系,通过与地震灾害评估系统使用的华北地区地震影响场模型进行对比分析,综合分析研究认为,建立分区烈度衰减关系更符合研究区域地震灾害的地域性特点,对于地震灾害快速评估具有重要的参考意义。  相似文献   

2.
收集内蒙古中西部地区MS 4.5以上地震目录,筛选具有完整等震线的地震资料作为研究对象,由此选取该地区15次中强地震事件33条等震线数据,采用线性反演方法,对烈度衰减关系进行回归分析,获得适用于内蒙古中西部地区的地震烈度衰减模型,结合华北地区烈度衰减关系进行对比分析,结果表明,该衰减关系符合本地区历史地震灾害分布地域性特点,对于震后快速评估和地震应急具有重要意义。  相似文献   

3.
中国大陆强震灾害范围的统计研究   总被引:1,自引:0,他引:1  
王健  张晓东 《中国地震》1998,14(3):26-31
强震的灾害范围是非常重要的地震学参数,它在地震灾害快速评估,地震保险及防震减灾等方面有着广泛的应用。本文全面,系统地收集了中国大陆宏观等震线资料,对没有地理坐标的等震线进行了数字化。精确计算了从1303年至1994年共183次强震的灾害范围,并对误差因素进行了分析。  相似文献   

4.
地震灾害损失初步评估方法研究   总被引:6,自引:2,他引:4  
通过搜集地震灾害及经济损失评估资料,研究地震灾害特征,总结经济损失规律,提取地震灾害损失评估经验模型。以此为基础,提出一种初步评估地震灾害经济损失的方法。研究震级与人员伤亡的关系,形成人员伤亡评估经验模型;采用适合本地区的人员伤亡评估经验模型,估算人员伤亡。研究历史地震烈度分布特征,根据震情速报的地点、震级初步确定地震灾区范围;按烈度分布的一般规律初步划分评估区;结合地震应急数据库统计不同评估区内房屋建筑面积,或者查阅当地年鉴统计不同评估区内人口数,按人均房屋建筑面积估算灾区房屋建筑面积;研究历史地震房屋建筑震害,给出房屋建筑地震破坏比经验模型(震害矩阵);按国家标准《地震现场工作第4部分:灾害直接损失评估》(2005)选取适合的损失比;收集不同结构类型房屋建筑的重置单价。遵循地震灾害损失评估原理,可以快速评估计算房屋建筑的地震灾害经济损失。研究历史地震中其他工程结构经济损失与地震灾害总损失的关系,给出其他工程结构经济损失占地震灾害总损失比例的经验模型,据此初步估计其他工程结构的经济损失。  相似文献   

5.
杨伟松    王长理    许卫晓    杜轲  于德湖   《世界地震工程》2021,(1):207-218
收集了我国南北地震带地区1970年~2012年的85次地震事件的烈度等震线资料,建立了震中烈度与震级之间的经验关系,利用长轴和短轴椭圆模型拟合得到了该地区的地震烈度衰减关系。同时还搜集整理了近年来基于我国各地区的地震资料,研究得到的地震烈度衰减关系,并将其中与南北地震带存在地域重合的研究结果与本文结果进行对比分析。该研究结果能够较好地反映南北地震带地区的地震烈度衰减规律,对该地区的地震灾害快速评估具有一定的参考意义。  相似文献   

6.
本文讨论了断层破裂烈度衰减模型,指出由它给出的烈度等震线的长轴向不很符合实际的等震线;在地震危险性分析中,该模型会高估高烈度的危险性。本文建议一个用等效破裂长度代替破裂长度的改进的断层破裂烈度衰减模型。统计数据和唐山地震的资料证实它能较好地拟合实际的等震线,从而改善地震危险性分析的结果。等效破裂长度的经验公式可表示为LnSe=a+bM-cl~3。它可以直接由历史地震等震线的资料统计得到。最后以河南小浪底水库坝址的地震危险性分析作为应用此烈度衰减模型的一个实例。  相似文献   

7.
无论是震害预测还是震害快速评估工作,都需要进行地震烈度定量化输入。通过地震烈度衰减关系,在地理底图上绘制地震烈度等震线,将地震影响烈度定量化到地理底图中的面与点中,从而为地震灾害快速评估提供依据。  相似文献   

8.
统计了重庆地区历史地震等震线长轴方位分布,主要为NE向。通过对地震活动、活动断裂分布、震源机制解的统计特征分析,指出历史地震等震线长轴方位与活动断裂的走向、震源机制解的一个节面走向基本保持一致,三者之间可相互印证。在地震应急工作中可快速建立等震线模型,从而确定灾区面积。  相似文献   

9.
河北及邻区地震烈度衰减关系研究   总被引:1,自引:1,他引:0  
地震震动的衰减关系在地震区划和工程场地的安全性评估过程中是不可或缺的。利用河北及周边区域历史地震的等震线资料,运用统计回归的分析方法,得到统计回归方程及地震烈度衰减关系,与其他烈度衰减关系进行对比分析,并与地震应急指挥技术系统软件及地震烈度分布资料进行对比,从而得到适用于河北及周边地区的地震烈度衰减关系。  相似文献   

10.
线源地震影响场计算模型   总被引:3,自引:1,他引:2  
传统的烈度衰减关系一般是由历史地震等震线资料拟合得到,但基于历史震例进行统计回归所得到的椭圆衰减模型往往不能够反映大地震时的地震衰减特点。尝试提出一种基于点源模型改进的线源地震影响场计算模型,引入地表破裂尺度对原有烈度衰减模型进行长轴上的修正,以期达到生成结果与强震实际烈度相拟合的目的,并可实现极震区震害的快速评估和计算。  相似文献   

11.
Modern earthquake loss models make use of earthquake catalogs relevant to the seismic hazard assessment upon seismicity and seismotectonic analysis. The main objective of this paper is to investigate a recently compiled catalog (National Institute of Meteorology or INM catalog: 412-2011) and to generate seismic hazard maps through classical probabilistic seismic hazard assessment (PSHA) and smoothed-gridded seismicity models for Tunisia. It is now established with the local earthquake bulletin that the recent seismicity of Tunisia is sparse and moderate. Therefore, efforts must be undertaken to elaborate a robust hazard analysis for risk assessment and seismic design purposes. These recommendations follow the recently published reports by the World Bank that describe the seismic risk in Tunis City as being beyond a tolerable level with an MSK intensity level of VII. Some attempts were made during the past two decades to assess the seismic hazard for Tunisia and they have mostly failed to properly investigate the historical and instrumental seismicity catalog. This limitation also exists for the key aspect of epistemic and random uncertainties impact on the final seismic hazard assessment. This study also investigates new ground motion prediction equations suitable for use in Tunisia. The methodology applied herein uses, for the first time in PSHA of Tunisia, seismicity parameters integrated in logic tree framework to capture epistemic uncertainties through three different seismic source models. It also makes use of the recently released version of OpenQuake engine; an open-source tool for seismic hazard and risk assessment developed in the framework of the Global Earthquake Model.  相似文献   

12.
Estimates of the earthquake ground motion intensity over a geographical area have multiple uses, that is, emergency management, civil protection and seismic fragility assessment. In particular, with reference to fragility assessment, it is of interest to have estimates of the values of different ground-motion intensity measures in order to correlate them with the observed damage. To this purpose, the present paper uses a procedure recently proposed in the literature to estimate the ground-motion intensity for the 2012 Emilia mainshocks, considering different ground motion intensity measures and directionality effects. Ground motion prediction equations based on different site effect models, and spatial correlation models are calibrated for the Emilia earthquakes. The paper discusses the accuracy of the shakemaps obtained using the different soil effect models considered and presents the obtained shakemaps as supplementary material. The procedure presented in the paper is aimed at providing ground motion intensity values for seismic fragility assessment and is not intended as a tool to estimate shakemaps for rapid emergency assessment.  相似文献   

13.
A computing environment for the seismic performance assessment of reinforced concrete frames has been developed in Matlab in combination with OpenSees. It includes several functions which provide calculations of the moment-rotation relationship of plastic hinges in columns and beams, rapid determination of simplified nonlinear structural models, the post-processing of the results of analyses and structural performance assessment with different methods. The user can add new functions to the PBEE toolbox in order to support additional procedures for the seismic performance assessment of RC frames, or can just change the rules for determining the moment-rotation relationship of plastic hinges in columns and beams, which are the main source of uncertainty in simplified nonlinear models. In the paper, the capabilities of the computing environment (PBEE toolbox) are first explained by focusing on the procedures for determining the moment-rotation relationship of plastic hinges. Different examples are then presented, starting with a comparison between the calculated response of a four-storey RC frame building and the response obtained in a pseudo-dynamic experiment. The calculated response was determined with the two different structural models which are later on used for the demonstration of the seismic performance assessment of the same structure by the N2 method. Lastly, seismic performance assessment of an eight-storey frame is performed by using incremental dynamic analysis with consideration of the modelling uncertainties.  相似文献   

14.
Spatial sensitivity of seismic hazard results to different models with respect to background seismic activity and earthquake occurrence in time is investigated. For the contribution of background seismic activity to seismic hazard, background area source with uniform seismicity and spatially smoothed seismicity models are taken into consideration. For the contribution of faults, through characteristic earthquakes, both the memoryless Poisson and the time dependent renewal models are utilized. A case study, involving the assessment of seismic hazard for the Bursa province in Turkey, is conducted in order to examine quantitatively the influence of these models on seismic hazard results. The spatial variation of the difference in Peak Ground Acceleration (PGA) values obtained from these different models is presented in the form of difference maps for return periods of 475 and 2475 years. Best estimate seismic hazard maps for PGA and Spectral Accelerations (SA) at 0.2 and 1.0 s are obtained by using the logic tree method.  相似文献   

15.
Research on seismic safety assessment has been the centre of great interest among the scientific community in recent years. Although the devastating impact of earthquakes on current society should be incentive enough to increase research, the development of more realistic mechanical behaviour models and the continuous enhancement of computation capabilities are paramount factors contributing a great deal to the increase of such interest. In this context, three research areas can be identified as currently leading to important developments: code related research, especially in Europe where new design codes are in the implementation process; risk analysis, namely concerning the definition of methodologies for safety assessment that involve the evaluation of the failure probability and could be included in future generations of codes; and experimental characterization of constitutive laws which provides support for the development and calibration of accurate and realistic numerical models for seismic analysis and for the adequate characterization of limit state capacities. The paper will present some of the current scientific research trends on these three seismic safety assessment related topics. Studies addressing the seismic safety assessment of structures, either probabilistically or based on code provisions, and that consider realistic nonlinear mechanical behaviour models will be focussed. Reference will also be made to experimental research on the seismic behaviour of structural elements, emphasizing its crucial role to support the development of numerical models simulating the effects of different seismic strengthening techniques. Finally, given the development of studies leading to new trends and perspectives for performance based earthquake engineering, a possible scenario for seismic design in the future is presented, emphasizing the key issues for its implementation.  相似文献   

16.
本文针对2021年5月21日云南漾濞6.4级地震,选取不同的地震烈度衰减关系模型,对各模型地震影响场评估结果与发布的地震烈度图进行对比分析,并对地震影响范围不确定性进行研究。选取多种死亡人数评估模型,分别计算各模型在不同地震影响场下的死亡人数、人口分布数量,探讨各地震影响场模型下的人口分布特征及影响人员死亡的主要因素。通过对比分析可知,导致此次地震灾害损失评估结果与真实地震现场结果不同的主要原因是地震影响场分布、人口分布、房屋建筑抗震能力偏差、地形地貌、次生灾害等多种因素不同。研究结果表明,有效提高地震灾害损失快速评估精确性的途径为提高地震影响场评估精度,提高人口分布、房屋建筑等数据空间分布评估精度,后期专家检验等。  相似文献   

17.
针对现阶段地震人员死亡评估模型在评估特定区域地震时评估结果误差较大的问题, 结合中国地震灾害特点、 人口分布情况等, 将中国大陆划分为西北、 西南和大陆东部三个地区, 并对各区域按照人口密度进行分级。 采用多元非线性回归方法, 选取震中烈度、 震区面积、 抗震设防烈度参数建立分区域的地震灾害人员死亡评估模型。 研究结果表明, 该模型在西北、 西南地区的验证结果较好, 适用于中国地震灾害情况, 可以用于震后快速盲评估, 在一定程度上能够避免评估不同震级、 相同震中烈度和人口密度的地震时, 出现相同结果的情况; 虽然该模型在震例较少的大陆东部地区以及城市直下型地震中评估结果需要进一步改进, 但为解决特定区域地震死亡评估中误差较大问题提供了思路, 能够为震后应急指挥和救援提供数据参考。  相似文献   

18.
Seismic fragility can be assessed by conducting incremental dynamic analysis (IDA). This study extends the current conditional mean spectrum (CMS)-based record selection approach for IDA by taking into account detailed seismic hazard information. The proposed method is applied to conventional wood-frame houses in Canada, across which dominant earthquake scenarios and associated hazard levels vary significantly. Effects due to different seismic environments, site conditions, CMS-based record selection methods, and house models are investigated by comparing various seismic fragility models. Moreover, relative impact of the key characteristics is evaluated in terms of seismic loss curve for a group of wood-frame houses. Importantly, a close examination of regional seismic hazard characteristics using seismic hazard curve and seismic deaggregation facilitates the deeper understanding of the impact of ground motion characteristics on seismic fragility. A comprehensive and systematic assessment of key uncertainties associated with seismic fragility is provided.  相似文献   

19.
The objective of this study is to evaluate the seismic hazard in Eastern Marmara Region using an improved probabilistic seismic hazard assessment methodology. Two significant improvements over the previous seismic hazard assessment practices are accomplished in this study: advanced seismic source characterization models in terms of source geometry and recurrence relationships are developed, and improved global ground motion models (NGA-W1 models) are employed to represent the ground motion variability. Planar fault segments are defined and a composite magnitude distribution model is used for all seismic sources in the region to properly represent the characteristic behavior of the North Anatolian Fault without the need for an additional background zone. Multi-segment ruptures are considered using the rupture model proposed by the Working Group on California Earthquake Probabilities (2003). Events in the earthquake catalogue are attributed to the fault zones and scenario weights are determined by releasing the accumulated seismic energy. The uniform hazard spectra at 10 % probability of exceedance in 50 years hazard level for different soil conditions (soil and rock) are revealed for specific locations in the region (Adapazar?, Düzce, Gemlik, Izmit, Iznik and Sapanca). Hazard maps of the region for rock site conditions at the selected hazard levels are provided to allow the readers perform site-specific hazard assessment and develop site-specific design spectrum for local site conditions.  相似文献   

20.
地震对建筑结构的损伤轻则影响建筑完整性,重则导致建筑崩塌。近几年,地震损伤评估问题得到地震工程研究领域的高度重视,但对点支式玻璃建筑结构的损伤评估研究较少。为此,构建一种点支式玻璃建筑结构地震损伤评估模型。采用基于HHT变换的结构损伤部位识别方法判断地震中点支式玻璃建筑损伤部位,建立点支式玻璃建筑结构地震损伤评估多元联系数模型,评估点支式玻璃建筑损伤部位的损伤情况。结果表明,该评估模型对某地区点支式玻璃建筑结构地震损伤评估情况与实际结果一致,且该模型可控性较强,评估范围全面,评估效率明显优于其他评估模型,应用价值较高。  相似文献   

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