Neural estimation of strong ground motion duration     

《Geofísica Internacional》2014,53(3):221-239

This paper presents and discusses the use of neural networks to determine strong ground motion duration. Accelerometric data recorded in the Mexican cities of Puebla and Oaxaca are used to develop a neural model that predicts this duration in terms of the magnitude, epicenter distance, focal depth, soil characterization and azimuth. According to the above the neural model considers the effect of the seismogenic zone and the contribution of soil type to the duration of strong ground motion. The final scheme permits a direct estimation of the duration since it requires easy-to-obtain variables and does not have restrictive hypothesis. The results presented in this paper indicate that the soft computing alternative, via the neural model, is a reliable recording-based approach to explore and to quantify the effect of seismic and site conditions on duration estimation. An essential and significant aspect of this new model is that, while being extremely simple, it also provides estimates of strong ground motions duration with remarkable accuracy. Additional but important side benefits arising from the model’s simplicity are the natural separation of source, path, and site effects and the accompanying computational efficiency.  相似文献   

Seismic microzoning from synthetic ground motion earthquake scenarios parameters: The case study of the city of Catania (Italy)     

《Soil Dynamics and Earthquake Engineering》2016

The city of Catania (Italy) in the South-Eastern Sicily has been affected in past times by several destroying earthquakes with high values of estimated magnitude. The seismogenic area to the south of Volcano Etna, known as Iblean Area, is placed between the African and the Euro-Asiatic plates on the west of the Ibleo-Maltese escarpment, to the south of the Graben of the Sicilian channel and on the east of the overlapping front of Gela. Basing on the seismic history of Catania, the following earthquake scenarios have been considered: the “Val di Noto” earthquake of January 11, 1693 (with intensity X-XI on MCS scale, magnitude M_W=7.41 and epicentral distance of about 13 km); the “Etna” earthquake of February 20, 1818 (with intensity IX on MCS scale, magnitude M_W=6.23 and epicentral distance of about 10 km). The soil response analysis at the surface, in terms of time history and response spectra, has been obtained by 1-D equivalent linear models for about 1200 borings location available in the data-bank of the central area of Catania of about 50 km², using deterministic design scenario earthquakes as input at the conventional bedrock.Seismic microzoning maps of the city of Catania have been obtained in terms of different peak ground acceleration at the surface and in terms of amplification ratios for given values of frequency.  相似文献   

2011年1月安徽安庆Ms4.8地震震源区三维速度结构与发震构造讨论     

陈安国  倪红玉  刘东旺  沈小七  刘泽民  郑海刚 《中国地震研究》2012,26(2):259-267

The Anqing MS4.8 earthquake occurred on January 19, 2011, with the epicenter lying in the foreland deformation belt along the Yangtze River of the lower Yangtze block. After the earthquake, the field work team surveyed and collected building damage data, calculating and obtaining more accurate intensity distributions. The focal mechanism of the main shock was calculated tentatively using digital seismic wave data from provincial digital seismic networks using the FOCMEC program and the first motions of P, SV and SH waves with their amplitude ratios. Using the location results of the main shock and aftershocks by the Anhui seismic network, combining the three-dimensional crust velocity structure imaging results of the focal region by seismic tomography, and referring on intensity distribution of the elliptic major axis’ predominant direction, we conclude by comprehensive analysis that the NE-trending Susong-Zongyang fault is possibly the causative fault of the Anqing earthquake.  相似文献   

新疆喀什地区新型石木结构房屋的模型抗震试验          下载免费PDF全文

张小平  陈平  赵冬  周铁钢 《地震工程学报》2008,30(1):42-45

对新疆喀什地区出现的新型石木结构房屋进行了1/4比例模型的地震反应试验的设计.概述了模型振动台试验方法,了解了此类结构的破坏形态,并对试验结果进行了初步分析,同时对结构进行了初步抗震性能评价.结果表明结构能够满足小震不坏、中震可修、大震不倒的抗震设防要求.  相似文献   

周至两次地震烈度异常的研究     

王卫东  张永志  吴芳  易学发  李少睿 《华南地震》2008,28(1):67-71

周至1988年ML4.3和1993年ML3．6级地震都在100km以外的柞水县城形成了高烈度异常区,从区域地质构造、场地条件和介质品质因子分布等方面研究了这一现象。结果表明：这两次地震造成的柞水高烈度异常与该区域地质构造、介质品质因子分布和柞水县城的局部地形条件密切相关。  相似文献   

A Preliminary Discussion on the Mechanism of Abnormal Intensity Zones of the M5.1 Wen'an Earthquake in 2006     

Zhang Suling  Zhao Jingyi  Lin Jie 《中国地震研究》2009,23(4):448-457

An earthquake measuring 5.1 on the Richter scale struck Wen'an county,Hebei Province on July 4,2006. No casualties have been reported,with only slight damage. The disaster level of this event is the slightest on the M4.9～5.1 events record tally since the CCDSN (China Center of Digital Seismic Network) was built in 1999. The epicenter intensity of this earthquake was low,while in areas like Beijing,which is 100km far away,abnormal high intensity zones appeared. This article discusses the reasons behind this abnormal phenomenon,with the diagrams of intensity isolines drawn by the intense seismic stations and networks in the capital circle area as references,as well as the seismogenic mechanism in the source,the seismic histories,the geological structures and the ray pathways of seismic waves in areas within 150km around the epicenter. It was concluded that the special dynamic and geological situations were the main causes for the lower intensity degree and slight damage in the epicenter area,but higher intensity in the surrounding areas.  相似文献   

汶川M_S8.0地震兰州烈度速报强震动记录与初步分析          下载免费PDF全文

刘旭宙  张元生  周民都  闵祥仪 《地震工程学报》2010,32(4):376-380

2008年汶川MS8.0地震有感地区范围大于1 000km。甘肃省十五期间在兰州市架设了50个强震台站用于实现市区范围内的强震动烈度速报,在本次地震中大多数台站都记录到了相应的强震动记录,其中最大单道加速度峰值记录为40.4cm/s2。本文展示了43个兰州烈度速报台站记录到的共129道本次地震强震动记录信息,并初步分析了兰州市加速度峰值分布和加速度峰值与土层厚度的对应情况。  相似文献   

山谷城市大气边界层结构及输送能力   总被引：14，自引：7，他引：7  

张强  吕世华  张广庶 《高原气象》2003,22(4):346-353

利用甘肃省—中国科学院科技合作项目“兰州市大气污染及对策研究”于2000年12月10～17日在兰州市城区用系留气球观测的大气边界层风速、风向、温度、湿度资料以及同期自动气象站观测资料和常规气象站辐射观测资料等,分析了山谷城市边界层大气的风速、温度、湿度结构特征,揭示了兰州市上空日夜维持的大气逆温的结构特征及其强度和分布特征的动态规律。提出了形成兰州山谷这种特殊大气逆温层的各种客观环境因素。最后还给出了在兰州市目前的小气候和地理环境条件下边界层大气的总体稳定度和Froude数的特征,由此初步定性讨论了兰州市大气边界层湍流运动和水平平流运动这两种主要输送形式的输送能力。  相似文献   

2003年11月13日甘肃岷县Ms5．2地震基本特征   总被引：5，自引：0，他引：5       下载免费PDF全文

郑文俊  刘小凤  赵广堃  马尔曼 《地震工程学报》2005,27(1):61-65

2003年11月13日在甘肃省岷县、临潭、卓尼三县交界地带发生了一次MS5.2地震,根据地震现场考察结果,归纳总结了本次地震的基本地震参数、烈度分布、震害特征、发震构造等基本特征,并分析总结了地震烈度偏高和震害严重的基本原因。  相似文献   

1739年银川一平罗8级地震灾害的历史辨析          下载免费PDF全文

白铭学  焦德成 《地震工程学报》2005,27(2):135-140

在查阅了大量有关1739年银川—平罗8级大震历史资料的基础上，结合建国以来对银川平原地震的研究成果，研究了1739年银川—平罗8级地震的地震烈度分布及其灾害特点。研究认为：该地震的发震构造为贺兰山东麓断裂，而极震区位于其东南的银川—平罗一带，与银川地堑第四纪沉降中心相吻合，这主要是受到工程地质条件的影响。其震害特点对减轻未来地震灾害、城市规划等都有参考价值。  相似文献