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1.
L. Cabañas J. M. Alcalde E. Carreño J. B. Bravo 《Bulletin of Earthquake Engineering》2014,12(5):1909-1932
The Lorca earthquake (southeast Spain) on May 11, 2011; Mw 5.1, and its aftershocks, have provided an important set of accelerograms recorded by the strong motion network of the Instituto Geográfico Nacional of Spain. It is particularly noticeable that the record obtained in Lorca town, very near of the fault rupture, presents a PGA value close to 0.37 g in the N30W component. This paper provides an overview of the strong motion data recorded during the Lorca seismic series, with particular attention to the accelerograms from the mainshock and foreshock and its characteristics. Due to the special circumstances of these two records, a more detailed processing has been required, in which various alternatives to adjust the baseline have been considered and analyzed. Based on this special processing, small residual displacements were obtained and reported in some of these cases. However, given the sensitivity of the process and the small obtained values, these findings should be taken with caution. Besides, response spectra have been analyzed and compared with design spectra proposed by the Spanish Seismic Code (NCSE-02) for the towns of Lorca, Alhama de Murcia and Mula. Large amplitude differences were observed in these spectra if compared to those recorded in Lorca. Also noteworthy is that the design spectra proposed for this town were exceeded by some horizontal directions of the response spectra. 相似文献
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This article points out some particular features conditioning seismic hazard assessments (SHA) in Spain, a region with low–moderate
seismicity. Although sized earthquakes occurred in the past, as evidenced by historical documents and neotectonic studies,
no large events occurred during the last decades. The absence of strong motion records corresponding to earthquakes with magnitude
larger than 5.5 is an important obstacle for the development of ground motion models constrained by local data, with the consequent
difficulty in SHA studies. In this paper, some recent developments aiming at providing solutions to these difficulties are
presented. Specifically, a strong motion databank containing a massive collection of accelerograms and response spectra from
different configurations source-path-site corresponding to earthquakes all over the world is introduced, together with software
utilities for its management. A first application of this databank is the development of specific ground motion models for
Spain and for the Mediterranean region that predict peak ground accelerations as a function of several definitions of magnitude,
distance and soil class. The predictive power of these ground motion models is tested by contrasting their estimates with
recently recorded ground motions. The comparison between our ground-motion models with others proposed in the literature for
other areas reveals a regular overestimation of the expected ground motions at Spanish sites by the non-local models. Consequently,
SHA studies based in external models may overestimate the predicted hazard at the Iberian sites. In the last part of the paper
a method for checking whether the response spectra proposed in the Spanish Building Code (NCSE-02) are consistent with actual
accelerometric data from recent low magnitude earthquakes is applied. The spectral shapes of the Spanish Building Code NCSE-02
are compared with the response spectral shapes deduced from the available accelerograms by normalising the response spectra
with the recorded PGA. It is appreciated that the NCSE-02 spectral shapes are exceeded by a large number of actual spectral
shapes for short periods (around 0.2 s), a result to be taken into account in further revisions of the NCSE-02 code. The issues
tackled in this work constitute not only an improvement for ground-motion characterisation in Spain, but also provide guidelines
of general interest for potential applications in other regions with similar seismicity. 相似文献
3.
A. Rivas-Medina S. Martínez-Cuevas L. E. Quirós J. M. Gaspar-Escribano A. Staller 《Bulletin of Earthquake Engineering》2014,12(5):2075-2093
A damage scenario modelling is developed and compared with the damage distribution observed after the 2011 Lorca earthquake. The strong ground motion models considered include five modern ground motion prediction equations (GMPEs) amply used worldwide. Capacity and fragility curves from the Risk-UE project are utilized to model building vulnerability and expected damage. Damage estimates resulting from different combinations of GMPE and capacity/fragility curves are compared with the actual damage scenario, establishing the combination that best explains the observed damage distribution. In addition, some recommendations are proposed, including correction factors in fragility curves in order to reproduce in a better way the observed damage in masonry and reinforce concrete buildings. The lessons learned would contribute to improve the simulation of expected damages due to future earthquakes in Lorca or other regions in Spain with similar characteristics regarding attenuation and vulnerability. 相似文献
4.
Dawei Lu Jianwen Cui Xiaojun Li Weiping Lian National Earthquake Infrastructure Service China Earthquake Administration Beijing China Earthquake Administration of Yunnan Province Kunming China Institute of Engineering Mechanics Harbin China 《地震学报(英文版)》2010,(1):95-100
The great MS8.0 Wenchuan earthquake has been the most destructive earthquake since 1949 in China. The earthquake occurred no more than half a year after the establishment of the National Strong Motion Observation Network System (NSMONS) of China; what is more, the epicenter was located in the area with dense strong motion observation stations so that a large number of strong motion records of the main shock were obtained. In this paper, 501 strong motion records from 167 observation stations are utilized to... 相似文献
5.
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
6.
本文利用青海地区近几十年的大地测量资料，探讨了该区现今地壳垂直形变与现代构造运动及强震活动之间的关系，认为青藏高原北部目前仍处于强烈的构造运动活跃期，判定了两处有可能是未来发生强震的场所，并对青藏高原北部强震成因提出了作者的看法。 相似文献
7.
On 11 May 2011, a M w ?=?5.1 earthquake shook the town of Lorca (SE Spain) causing a disproportionately large damage for its magnitude. In order to contribute to knowledge of the behavior of the active faults present in the region and define the parameters which control their motion, we made a detailed study of the rupture process of this earthquake from inversion of body waves at regional and teleseismic distances. Ground motion displacements obtained in this way are in agreement with near-field strong motion data and GPS observations recorded in Lorca. We have obtained a partly bilateral rupture propagating to WSW (238°, 54°, 59°) with 27 cm of maximum slip and shallow focus (4 km). The fault plane orientation corresponds to that of the Cejo de los Enamorados Fault located NE of the Lorca town and parallel to the Alhama de Murcia Fault. The distribution of slip on the fault plane can explain the lack of any observed surface rupture as we found that the rupture started at 4-km depth along a plane dipping at 54°, with motion propagating upward to stop at 1.5 km below the surface. The strong motion and GPS data recorded near the epicenter are in agreement with the maximum slip on the fault. Directivity effects and the extreme shallowness of the rupture could explain the considerable damage that the earthquake caused in the town of Lorca. 相似文献
8.
The duration of strong motion has a significant influence on the severity of ground shaking. In this work, a combination of average values of four geophysical properties of site (Standard Penetration Test (SPT) blow count, primary wave velocity, shear wave velocity, and density of soil) including hypocentral distance of less than 50 km and magnitudes more than 5.0 from Japanese ground motion records were used for development of neural network model, to estimate duration of strong ground motion. Since majority of strong motion databases provide only average shear wave velocity for site characterization, an attempt has also been made to train the neural network with magnitude, hypocentral distance and average shear wave velocity as three input variables. Results obtained from this study show that the duration of strong motion is mostly dependent on average shear wave velocity rather than other geophysical properties of site. 相似文献
9.
Characterization of Earthquake Strong Ground Motion 总被引：1，自引：0，他引：1
— Some underwater landslides are triggered by strong ground motions caused by earthquakes. This paper reviews current concepts and trends in the characterization of strong ground motion. Improved empirical ground motion models have been derived from a strong motion data set that has grown markedly over the past decade. However, these empirical models have a large degree of uncertainty because the magnitude-distance-soil category parameterization of these models often oversimplifies reality. This reflects the fact that other conditions that are known to have an important influence on strong ground motions, such as near-fault rupture directivity effects, crustal waveguide effects, and basin response effects, are not treated as parameters of these simple models. Numerical ground motion models based on seismological theory that include these additional effects have been developed and extensively validated against recorded ground motions, and used to estimate the ground motions of past earthquakes and predict the ground motions of future scenario earthquakes. 相似文献
10.
强震动观测仪器面临的机遇和挑战 总被引：1，自引：1，他引：0
本文介绍了国内外强震仪、力平衡加速度计、烈度计、MEMS加速度仪等强震动观测仪器的发展历史与现状,概述了强震动记录中典型异常波形产生的原因和力平衡加速度计的仪器响应误差及校正,建议了解决强震仪器缺陷的措施,分析了强震仪在强震动观测发展中面临的机遇和挑战。研究结果如下:① 进行强震动记录异常波形的研究是有针对性改进现有强震仪存在问题的很好途径;② 早期数字强震仪（力平衡加速度计频带范围0至30Hz）获取的强震动记录应进行仪器校正;③ 应跟踪强震动观测新方法和相关领域新技术,发展MEMS加速度仪和光纤加速度仪等新型仪器。 相似文献
11.
This paper briefly summarizes the works in the processing of strong ground motion data, the factors affecting strong ground motion, the modeling of strong ground motion and the calculating of broad-band response spectrum which have been done recent years by engineering seismologists and seismologists of China. In addition, we think back to the international cooperation in strong ground motion of the recent years and make some expectations for the future. 相似文献
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The great
13.
为解决强震仪在较恶劣环境下的使用问题,浙江省地震局结合本省强震仪观测环境特点,研制小型室外加速度计观测罩,保障强震仪土层自由场观测。该技术目前已由浙江省十多个地震台站安装使用,实例证明,该观测罩具有体积小、制造方便、使用寿命长、防水隔震等优点,可为强震仪提供良好的工作环境。 相似文献
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To study the ground motion levelassociated with historical earthquakeslocated in Southern Spain, we have chosen ascenario placed in the Poniente Almeriense(Southeast Spain). In this zone, somerelevant historical earthquakes haveoccurred, such as those of 1522, 1804 and1910. In particular, the earthquakes of 1804 and 1910 the estimated and calculatedmagnitudes are of M = 6.3. Those earthquakestook place near the epicentral zone of aseismic series happened in 1993–94. As partof this series, two earthquakes with M5were recorded by strong ground motioninstruments on 23rd December 1993, and 4th January, 1994 at Adra, Almeríaand Motril. We have used the accelerationrecords as empirical Green functions inorder to simulate the expected groundmotion associated with a hypotheticalearthquake of magnitude M = 6.3 like those of1804 and 1910. The simulations have beencarried out for three sites (Almería,Adra and Motril) using three differentapproaches. A total of 30 simulations, foreach approach, have been carried out foreach ground motion component in each site.The peak ground acceleration (PGA) and theresponse spectra are compared with thevalues obtained through empiricalrelationships for the distances and soilconditions corresponding to the threechosen sites. The results of thesimulations show that the horizontal PGAcould exceed the values observed in23/XII/93 and 4/I/94 by a factor of 5–8,surpassing in some cases the value of 140gals. Besides, some of the peak spectralaccelerations simulated reach Samax =400 gals, Adra being the location where thehighest values of amax andSamax are reached, due to the nearnessof this station to the epicentres of 23/XII/93 and 4/I/94. At Almeria, the PGAvalues reach 40 gals, which may beconsidered as input in the bedrock. InMotril, the PGA surpass a value of 130gals, considering as due to a strong localsite effect. Finally, the peak groundacceleration (PGA) and the response spectraobtained with the simulations have beencompared with other values estimated through empirical relationships for similarconditions. The conclusions about theexpected ground motion levels have animportant application aimed at the revisionof the maximum acceleration and responsespectra of the Spanish building Code,NCSE-94. 相似文献
17.
Zbigniew Zembaty 《地震工程与结构动力学》1988,16(8):1189-1200
An analysis of the influence of strong motion duration on the response spectra is presented. The analysis is based on the concept of evolutionary power spectral density and first passage estimations for non-stationary random vibrations. To compare the response for different durations the criteria of constant Arias intensity and constant excitation level have been applied. The paper presents a numerical analysis of the effect of strong motion duration on various response statistics for a linear oscillator. Results indicate a decrease of peak response and first passage probability with increasing strong motion duration for constant Arias intensity. 相似文献
18.
Since the late 1970s, the dynamic range and resolution of strong motion digital recorders have leaped from 65 to 135 dB, opening new possibilities for advanced data processing and interpretation. One of these new possibilities is the calculation of permanent displacement of the ground or of structures, associated with faulting or with non-linear response. Proposals on how permanent displacements could be recovered from recorded strong motion have been published since 1976. The analysis in this paper concludes that permanent displacements of the ground and of structures in the near-field can be calculated provided all six components of strong motion (three translations and three rotations) have been recorded, and the records are corrected for transducer rotation, misalignment and cross-axis sensitivity. 相似文献
19.
随着我国强震动观测数据数量和质量的大幅提高, 破坏性地震发生后所观测到的强震动记录也在试验性地转化为仪器烈度数据． 本文将强震动记录引入应急性的生命损失快速评估, 借助已有的地震应急灾害损失快速评估模型的表达方法, 提出了一种将仪器烈度概率密度函数和生命损失函数相结合的地震人员伤亡快速评估方法． 通过确定仪器烈度的概率密度, 并结合四川地区已有房屋建筑易损性研究成果, 建立了考虑建筑地震易损性并与烈度相关的地震生命损失快速评估函数, 并利用汶川地震的强震动记录对本文提出的生命损失快速评估方法进行评估计算. 结果表明, 该方法的计算结果与实际震害损失结果颇为一致, 说明了该方法的可行性, 因而能够及时为地震应急救援提供可靠信息． 相似文献
20.
Ruizhi Wen Zhenghua Zhou Xiaojun Li Cheng Yang Yuhuan Wang Quan Liu Xiaotao Yin Mindu Zhou Jianwen Cui Institute of Engineering Mechanics China Earthquake Administration Harbin China Earthquake Administration of Gansu Province Lanzhou China Earthquake Administration of Yunnan Province Kunming China 《地震学报(英文版)》2009,(2):181-187
In this paper, the mobile strong ground motion observation for the destructive earthquake is introduced.Considering the characteristics and its spatial distributions of aftershock, 59 strong ground motion instruments were installed along the Longmenshan fault area, and more than 2 000 records have been accumulated.It shows that it is necessary to per-form the mobile strong ground motion observation after the destructive earthquake, and the precious collected data could be applied for further research. 相似文献