共查询到18条相似文献，搜索用时 140 毫秒
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2021年2月13日,日本福岛近海发生MS7.1地震,震中距海岸线约70 km,震源深度接近60 km,造成了较大范围的震害影响。考虑地震应急及地震动强度特征预测的应用前景等,利用经验格林函数法快速估计了本次地震的高频地震动（1.0～20.0 Hz）空间分布特征及加速度时程,并结合实际地形、场地覆盖层等信息对部分台站地震动模拟结果进行修正,最终获得较可靠的地震动预测结果。研究结果表明,在具备合适小震记录时（余震及前震）,可较准确地再现大震的高频地震动主要特征,模拟结果与真实记录拟合较好;地震动模拟过程中需考虑盆地等特殊地形及覆盖土层对地震动的放大作用影响,这也是未来利用经验格林函数法合成大震时需重点考虑的因素。 相似文献
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2020年10月22日11时03分37秒四川省绵阳市北川县发生MS4.7地震,四川强震动台网与预警烈度速报台网在震区建成较密集的台站,获取了532组三分量加速度记录,有助于开展区域地震动衰减和地震动特征研究.本文对强震记录进行常规处理后计算出强震动记录的相关参数,利用克里金插值方法得到地震动峰值加速度PGA和峰值速度PGV的空间分布图,长轴呈北西—南东方向.分析强震动记录PGA、PGV随距离的衰减规律,与常用衰减关系预测值进行对比,此次地震PGA的衰减特性与俞言祥和汪素云(2006)提出的中国西部地区水平向基岩加速度衰减关系有较好的一致性.北川MS4.7地震获得的密集强震动记录为建立区域衰减关系,以及开展基于经验格林函数方法(EGFM)再现大震强地震动场展布等研究提供了重要的数据支撑. 相似文献
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本文选取2016年4月16日日本熊本县MJ7.3 （MW7.0）地震近场区域内K-net地震台网的47个强震台站所记录的加速度数据，运用经验格林函数法模拟分析此次地震主要的工程地震参数并给出了各工程参数的空间分布。通过对比分析得到结论如下:① 地震动时程的基本频谱的模拟结果较好，尤其是1—15 Hz的高频段内；② 在震源距小于50 km范围内，峰值加速度和阿里亚斯强度的观测值与模拟值拟合较好，二者在近场区域均以椭圆形向周围扩散衰减，且阿里亚斯强度的模拟值整体大于观测值；③ 卓越周期拟合整体较好，但在局部区域存在较大差异，模拟结果难以表征场地环境的复杂性。 相似文献
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2017年8月8日在四川阿坝州九寨沟县发生了MS 7.0地震，这是继2008年四川汶川MS 8.0地震和四川芦山MS 7.0地震后在此地区发生的又一强震。本研究对此次地震中的66组主震记录进行了常规校正处理，基于此分析了此次地震中典型台站——九寨百合台站的地震动特征，并通过地震动的峰值加速度、反应谱参数分析了近场效应特征。研究结果表明:九寨百合台站的三分量峰值加速度都超过了100 gal，而地震动持时相对较短，并且三分量反应谱在短周期大于Ⅷ度多遇地震设计谱，小于Ⅷ度罕遇地震设计谱；由于九寨沟地震属于典型的走滑型地震，因此地震动参数的方向性特征不明显；九寨沟地震的地震动的峰值加速度以及反应谱谱值小于同等震级的芦山地震，并且小于几个典型衰减关系的预测值。对九寨沟地震的地震动参数特征研究表明，此次地震是一次震级较大、但灾害损毁程度较低的地震。 相似文献
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汶川M_W7.9地震的发生震惊了中国乃至全世界,不仅仅因为该地震震级巨大,还因为其可怕的伤亡。评估汶川M_W7.9地震的复杂性及破坏力需对其地震特征进行研究。本文运用经验格林函数方法(EGF)模拟了地震的强地震动。首先,选取了4个震级为M_W4.9和M_W5.0的余震,对这些余震的运动利用格林函数进行了模拟。通过模拟,可以估算出包括断层规模和应力降在内的余震震源参数。然后,通过试错法正演模拟得出M_W7.9地震凹凸体(强震动生成区)的震源模型。为验证该震源模型的准确性,运用经验格林函数方法模拟合成了9个台站的强地震动。将模拟得出的强地震动与观测记录到的加速度波形、速度波形和拟加速度反应谱相比较。尽管有一些差异,但在大部分台站,合成的强地震动与观测记录结果相吻合。在模拟得出的震源模型中,断层面上3个凹凸体的应力降约为10MPa,而凹凸体面积与破裂面积比为0.24,接近经验关系式得出的结果0.22。 相似文献
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综合考虑震中地区地质构造背景、震源机制解结果、余震分布以及我国西部地区地震动参数衰减特征,运用考虑场地效应的震动图快速生成方法,将收集到的62组强震台站的峰值加速度作为插值使用,估计了2014年8月3日云南鲁甸MS6.5地震峰值加速度震动图. 利用地震后获得的强震记录计算了强震台站观测值与借助经验性衰减关系得到的估计值之间的系统偏差,校正了缺少台站地区借助经验性衰减关系得到的估计值,获得了校正后的峰值加速度分布图. 结果显示,鲁甸MS6.5地震的地震动峰值加速度随距离的衰减速度比前人对我国西部衰减统计的结果更快,对数偏差校正的结果更符合本次地震的衰减规律. 校正后的峰值加速度大于40 cm/s2的区域面积近8000 km2,比未经校正的峰值加速度大于40 cm/s2的面积减小了40%左右. 相似文献
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由于震中附近强震台分布不均，文中联合使用近场2个国家强震动观测台网的强震台和7个云南地震预警台网烈度台的强震记录，采用经验格林函数法构建了特性化震源模型，并利用此模型对近场强震动进行了模拟。结果表明：烈度台的记录可与强震台的记录联合，共同作为强震动模拟的对象，但应注意区分二者的有效频带；在0.20～30.0Hz频带，在53YBX台处的NS分量上，模拟结果的伪加速度反应谱较好地再现了0.1s处的峰值，在EW分量上，合成的速度波形虽然幅值较低，但较好地再现了速度脉冲波段；在53DLY台处的合成波形较好地再现了约2s的长周期地震动；在0.50～30.0Hz频带，合成波形和反应谱与信噪比较高的烈度台的记录较为一致。文中确定的用于模拟强震动的特性化震源模型由一个强震动生成域构成，其面积和相应的短周期范围内加速度震源谱的水平段幅值与地震矩的关系均遵循经验标度律。 相似文献
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考虑地震环境的人造地震动合成方法 总被引：9，自引：0，他引：9
本文将经验格林函数法和人造地震动反应谱拟合技术有机地结合起来,提出了一种新的人造地震动方法。利用已有的场地附近的小震记录合成可能发生的大震地面运动,以此作为人造地震动的初始值,通过反复调整初始加速度的傅氏幅值谱来拟合给定的目标反应谱,以得到满足精度要求的人造地震加速度时程。本文方法可以考虑地震环境和局部场地对地震动的影响。所合成的地震加速度时程具有时间强度和频率含量的非平稳特征,并且不需要人为规定强度包线。 相似文献
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余震是由主震孕育而来，两者之间存在着一定的关联性，如何构造主余震型地震动模型，是工程结构抗震分析的基础。着眼于地震动的工程特性，根据主余震之间的峰值加速度、强震持时、场地卓越频率等要素，分别建立主震和余震自身的演变功率谱模型，基于非平稳随机过程的谱表示，通过引入随机函数降维模拟方法，实现仅用三个基本随机变量即可精确模拟主余震型地震动过程。研究表明，采用该降维模拟方法的效率和精度均满足工程需求，且与实测主余震型地震动记录的反应谱和幅值谱拟合一致，验证该模型与方法的优越性，为工程结构在主余震型随机地震作用下的抗震分析提供有效途径。 相似文献
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以往的经验格林函数方法存在着两个问题:一是要求大小地震需满足"相似"或"准相似"条件,这就限制了经验格林函数方法的适用范围。二是对大地震断层面的位错不均匀性考虑得不充分,而实际上大地震断层的位错一般是不均匀的。本文在假定大小地震不满足"相似"和"准相似"以及大地震断层面位错不均匀的前提下,对经验格林函数方法进行了改进,并应用于卢龙地震的模拟,模拟的结果与记录符合得比较好,说明改进的经验格林函数方法可以用来估计场地地震动过程。 相似文献
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Simulation of strong earthquake characteristics of a scenario earthquake (MS7.5) based on the enlightenment of 2022 MS6.9 earthquake in Menyuan 
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下载免费PDF全文 The Menyuan area is an important transportation hub in the Hexi Corridor. The Menyuan MS6.9 earthquake that occurred on January 8, 2022 had a major impact on the local infrastructure and transportation of this region. Due to the high possibility of similar strong earthquakes occurring in this area in the future, preliminary assessment of the seismic intensity characteristics of destructive earthquakes in this region is essential for effective disaster control. This paper uses the empirical Green′s function (EGF) method as a numerical simulation tool to predict the ground motion intensity of Datong Autonomous County under the action of the scenario earthquake (MS7.5). Seismic records of aftershocks of the 2016 Menyuan MS6.4 earthquake were used as Green’s functions for this simulation. The uncertainties associated with various source parameters were considered, and 36 possible earthquake scenarios were simulated to obtain 72 sets of horizontal ground motions in Datong County. The obtained peak ground acceleration (PGA) vs. time histories of the horizontal ground motion were screened using the attenuation relationships provided by the fifth-edition of China's Seismic Ground Motion Parameter Zoning Map and the NGA-West2 dataset. Ultimately, 32 possible acceleration-time histories were selected for further analysis. The screened PGA values ranged from 78.8 to 153 cm/s2. The uncertainty associated with the initial rupture point was found to greatly affect the results of the earthquake simulation. The average acceleration spectrum of the selected acceleration-time history exceeded the expected spectrum of a intermediate earthquake, which means that buildings in Datong County might sustain some damage should the scenario earthquake occur. This research can provide reliable ground motion input for urban earthquake damage simulation and seismic design in Datong County. Growing the dataset of small earthquakes recorded in this region will facilitate the large-scale simulation of ground motions under different earthquake scenarios. 相似文献
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本文以美国加州3次破坏性地震和2008年中国汶川Ms8.0地震中所获得的强震记录作为数据源,应用最小二乘法进行线性回归,得到了不同地震动参数与烈度间的相关性.统计发现,在地面加速度峰值、地面速度峰值等16种描述地震动强度的参数中,烈度识别正确率及相关性最好的两个参数分别是标准累积绝对速度和谱烈度. 相似文献
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Broadband ground motion simulation using a hybrid approach of the May 21, 2021 M7.4 earthquake in Maduo,Qinghai, China 下载免费PDF全文
下载免费PDF全文 Yijun Liu Xiaofen Zhao Zengping Wen Jie Liu Bo Chen Chunyao Bu Chao Xu 《地震科学（英文版）》2023,36(3):175-199
In this study, the broadband ground motions of the 2021 M7.4 Maduo earthquake were simulated to overcome the scarcity of ground motion recordings and the low resolution of macroseismic intensity map in sparsely populated high-altitude regions. The simulation was conducted with a hybrid methodology, combining a stochastic high-frequency simulation with a low-frequency ground motion simulation, from the regional 1-D velocity structure model and the Wang WM et al. (2022 ) source rupture model, respectively. We found that the three-component waveforms simulated for specific stations matched the waveforms recorded at those stations, in terms of amplitude, duration, and frequency content. The validation results demonstrate the ability of the hybrid simulation method to reproduce the main characteristics of the observed ground motions for the 2021 Maduo earthquake over a broad frequency range. Our simulations suggest that the official map of macroseismic intensity tends to overestimate shaking by one intensity unit. Comparisons of simulations with empirical ground motion models indicate generally good consistency between the simulated and empirically predicted intensity measures. The high-frequency components of ground motions were found to be more prominent, while the low-frequency components were not, which is unexpected for large earthquakes. Our simulations provide valuable insight into the effects of source complexity on the level and variability of the resulting ground motions. The acceleration and velocity time histories and corresponding response spectra were provided for selected representative sites where no records were available. The simulated results have important implications for evaluating the performance of engineering structures in the epicentral regions of this earthquake and for estimating seismic hazards in the Tibetan regions where no strong ground motion records are available for large earthquakes. 相似文献
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中强地震活动区地震动衰减关系的确定 总被引：3，自引：0，他引：3
地震动衰减关系是影响地震安全性评价特别是地震区划结果的重要因素.我国现行的地震动衰减关系主要是依据6级以上地震的地面运动资料得到的,并没有考虑中强地震的衰减特性.为此,文中利用现有的烈度资料和其他可供参考的研究成果来建立我国中强地震活动区的地震动衰减关系.收集了我国华中、华南、东北等地区的51次地震的烈度等震线资料,运用单随机变量加权最小二乘回归法得到中强地震活动区烈度衰减关系.然后以美国西部地区为参考地区,运用缺乏地震动参数的地震动估计方法-地震对映射法得到中强地震活动区峰值加速度和有效峰值加速度衰减关系.最后,通过与我国强地震区和中强地震区已有的烈度衰减关系和地震动衰减关系的对比,验证了得出的我国中强地震活动区烈度衰减关系和地震动衰减关系的合理性. 相似文献
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The 2003 Bam, Iran, earthquake caused catastrophic damage to the city of Bam and neighboring villages. Given its magnitude (M w ) of 6.5, the damage was remarkably large. Large-amplitude ground motions were recorded at the Bam accelerograph station in the center of Bam city by the Building and Housing Research Center (BHRC) of Iran. We simulated the Bam earthquake acceleration records at three BHRC strong-motion stations—Bam, Abaraq, and Mohammad-Abad—by the empirical Green’s function method. Three aftershocks were used as empirical Green’s functions. The frequency range of the empirical Green’s function simulations was 0.5–10 Hz. The size of the strong motion generation area of the mainshock was estimated to be 11 km in length by 7 km in width. To estimate the parameters of the strong motion generation area, we used 1D and 2D velocity structures across the fault and a combined source model. The empirical Green’s function method using a combination of aftershocks produced a source model that reproduced ground motions with the best fit to the observed waveforms. This may be attributed to the existence of two distinct rupture mechanisms in the strong motion generation area. We found that the rupture starting point for which the simulated waveforms best fit the observed ones was near the center of the strong motion generation area, which reproduced near-source ground motions in a broadband frequency range. The estimated strong motion generation area could explain the observed damaging ground motion at the Bam station. This suggests that estimating the source characteristics of the Bam earthquake is very important in understanding the causes of the earthquake damage. 相似文献
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<正>Ground motion records are often used to develop ground motion prediction equations(GMPEs) for a randomly oriented horizontal component,and to assess the principal directions of ground motions based on the Arias intensity tensor or the orientation of the major response axis.The former is needed for seismic hazard assessment,whereas the latter can be important for assessing structural responses under multi-directional excitations.However,a comprehensive investigation of the pseudo-spectral acceleration(PSA) and of GMPEs conditioned on different axes is currently lacking.This study investigates the principal directions of strong ground motions and their relation to the orientation of the major response axis, statistics of the PSA along the principal directions on the horizontal plane,and correlation of the PSA along the principal directions on the horizontal plane.For these,three sets of strong ground motion records,including intraplate California earthquakes,inslab Mexican earthquakes,and interface Mexican earthquakes,are used.The results indicate that one of the principal directions could be considered as quasi-vertical.By focusing on seismic excitations on the horizontal plane,the statistics of the angles between the major response axis and the major principal axis are obtained;GMPEs along the principal axes are provided and compared with those obtained for a randomly oriented horizontal component;and statistical analysis of residuals associated with GMPEs along the principal directions is carried out. 相似文献
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北京时间2017年8月8日21时19分在四川阿坝州九寨沟县（北纬33.2°、东经103.8°）发生了7.0级地震，作者利用新提出的震源破裂过程控制的NNSIM随机有限断层方法，对震中约100 km范围内强地面运动进行了情景构建，并与研究区范围内的8个强震测震台观测记录进行了加速度、速度、反应谱对比，对比的一致性说明模拟过程中所应用的各种震源参数适合九寨沟7.0地震的近震源强地面运动重建.论文的后半部分基于相同参数模拟了九寨沟7.0级地震的近震源强地面运动场的空间分布，结果显示此次地震强地面运动的PGA、PGV以及反应谱分布均呈现出以震中为圆心的圆形分布，不具有大地震沿断层走向的分布特点.论文最后关于反应谱的讨论，揭示了此次九寨沟县城灾害不重的直接原因. 相似文献