远程协同结构试验方法研究与发展

本文对美国“NEES计划”、欧洲“减轻地震风险的欧洲网络”研究计划、日本E-Defense建设及其远程协同试验、中国台湾地区国家地震工程研究中心ISEE计划和由国家基金委资助的正在进行的重点项目“现代结构拟动力地震模拟协同试验方法与系统”(HQH-NSER)进行了简要介绍,叙述了在远程协同试验研究中的一些关键问题及其应用领域,并对未来的发展趋势作一展望。     

寻找薄弱环节,推动日本地震预报的研究

本文根据日本《每日新闻》的连载报道,从信息共有,对前兆现象的研究、重视活断层的研究、正确对待研究人员的个人预报信息等几个方面介绍了目前日本预报研究的现状及存在的一些薄弱环节。     

E-Defense振动台试验预测性分析比赛的研究综述

文中介绍了日本E-Defense的足尺钢框架振动台试验预测性分析比赛的情况,研究了分析人员对该钢框架结构所采用不同的数值分析方法。分析方法大致分为纤维模型,塑性铰模型,微观单元模型及结构协同分析方法4种。纤维模型与塑性铰模型属于宏观单元,假定条件较多但自由度数少适用于整体结构分析。微观单元假定条件较少,力学概念明确,能准确反映构件局部破坏,整体分析比较困难。结构协同分析方法属于混合单元法,通过不同单元甚至不同程序模拟各个构件,再通过主程序组装总刚度进行动力分析,该方法发挥了微观单元和宏观单元各自的优点。     

地震宏观前兆特征

地震宏观前兆异常，如动物行为异常、地下水和温泉变化等的性质，是根据与日本某些大地震有关的大量资料进行了研究的。     

日本伊豆半岛群发地震及日本地震观测技术与地震预报研究概况

１９９７年３月３－９日、日本伊豆半岛东岸发五群发地震，共计８３２８次，最大震级为５．７。综合介绍了这次震群的破坏情况，发震和构造背景，以及１９８９年６－９月伊豆半岛群发地震的实例研究概况和历史地震记录，简述了日本现代地震观测技术与地震预报研究工作。     

日本MW9.0地震后沂沭断裂带两侧块体相对运动及对地震活动的影响

基于连续GPS数据,利用滑动块体模型研究了日本M_W9.0地震前后沂沭断裂带两侧块体连续的相对运动状态,并研究其对区域地震活动的影响,结果表明日本地震以来：1）两侧块体呈右旋走滑兼挤压状态,平均走滑、挤压速率分别为0.9±0.1 mm·a^-1和-0.7±0.1 mm·a^-1,相比日本地震之前,运动过程更具起伏特征,可能与日本地震前后俯冲带两侧板块间相互运动状态的改变有关;2）沂沭断裂带两侧地区地震活动频次N、总释放能量折算震级M、地震活动度S值、地震b值与两侧块体相对运动的相关系数分别为0.66、0.69、0.74、-0.6,T检验显示相关性显著.在研究区地震能量集中释放阶段两侧块体相对运动方向和研究区主压应力方向一致,相对运动速率和地震活动强度变化具有同步特征,两侧块体相对运动对区域地震活动具有控制作用;3）莱州序列和乳山震群的发生可能与两侧块体相对运动促进的局部区域应力调整有关.     

地震信息紧急传输系统的研制--原子能研究所实时地震防灾研究

作为日本科学技术厅"地震综合拓展研究"的一个环节,日本原子能研究所于1996年开始大力推进"安全抗震、防灾的研究".该研究包含4个研究项目:①与包括原子能设施在内的产业设施的安全抗震有关的地震危险性评价和②设备减震研究;③与防止地震灾害有关的实时地震防灾和④紧急时刻信息传输方法.下面介绍其中的"实时地震防灾研究"的研究计划.     

1995年1月17日日本兵库县南部地震概况综述

１９９５年１月１７日,强烈的日本兵库县南部地震袭击了日本近畿地方的广大地区,这次灾难性的地震是半个世纪以来在日本发生的规模最大的一次内陆地震,它使日本遭受了一次出乎意料的严重破坏,打破了“日本安全”的神话,将对今后的地震预报和防灾对策研究产生重大的影响,因此,这次地震引起了日本和世界各国的极大关注。本文将对这次地震作一综合介绍。     

有关兵库县南部地震的调查研究工作简介

有关兵库县南部地震的调查研究工作简介１．探明活断层深部构造和动态特性的计划（断层解剖计划）为了进一步推动地震预报研究，日本全国各大学协手在兵库县南部地震的震源断层附近进行如下的观测和实验研究。在该项研究中，将利用地球物理及地球化学的方法综合探明活断层...     

日本广岛6．4级地震及地震工作概述

综合介绍了2001年3月24日日本广岛发生6．4级地震的破坏情况，发震和构造背景及历史地震记录；概述了日本的地震灾害，地震观测技术和“地震预计计划”的进展，并阐述了日本未来10年地震调查研究的方针政策。     

Dynamic behaviors of underground structures in E-Defense shaking experiments

In mitigating disasters, underground structures are required to play an important role because they generally perform well even under large seismic loads and can be used as bases for reconstructing damaged cities. Underground structures compose a network, and therefore, disconnections caused by localized damage may induce critical malfunctions. To investigate this problem, a series of shake table tests using large-scale soil-underground structure models was performed at E-Defense, Japan in 2012. The intent of the tests was to capture detailed localized behaviors of underground structures around inground joints and boundaries between two different soil strata. In the experiments, significant failure developed at an inground joint due to displacement of the surrounding soil. In addition, noticeable localized behaviors, such as conversion of horizontal ground displacement to vertical bending of a tunnel appeared around the inground joints. Also, it was found that a flexible segment along underground structures is effective in mitigating damage to those underground structures, but only in its immediate vicinity.     

Lessons and Questions from Thirty Years of Testing the Precursory Swarm Hypothesis

In 1976 Frank Evison identified the first examples of earthquake swarms as long-term precursors of main-shock events, and thereby discovered the predictive scaling relations of long-term seismogenesis. From this time on, forecasting became the main focus of his research. After learning from an early attempt to communicate forecasts confidentially to government, he recognised the importance of hypothesis testing, and the precursory swarm hypothesis was cast in a form similar to a regional likelihood model. Tests of its performance relative to a stationary Poisson model at M ≥ 5.8 in New Zealand were begun in 1977. The initial hypothesis was that of a 1–1 relation between swarms and main-shock events. Following a study of the Japan catalogue, the generalised swarm hypothesis, in which multiple swarms were precursory to multiple main-shock events, was formulated. Tests of this form of the hypothesis at M ≥ 6.8 were initiated in a region of surveillance east of Japan in 1983. Eventually the generalised hypothesis was adopted in New Zealand also. In 1999, tests were begun in a region of Greece. In 1994–1995, several main-shock events favourable to the swarm hypothesis occurred, however four main-shock events near Arthur’s Pass, New Zealand, occurred without precursory swarms. Subsequent analysis showed that events called “quarms”, which were similar to swarms but more protracted in time, had preceded these events. This led to the proposal of a qualitative physical process to account for swarms, quarms and the predictive relations: A three-stage faulting process, in which a major crack induces aftercracks in its neighbourhood, just as a main shock induces aftershocks. An inference from this process was that the most general long-term precursor should be an increase of seismicity at similar magnitudes to the eventual aftershocks. It turned out that such a precursory scale increase nearly always occurs before major earthquakes and conforms to the predictive scaling relations. Setting aside the problem of identifying the scale increase before the major earthquake, the EEPAS (Every Earthquake a Precursor According to Scale) forecasting model was formulated. The success of this relatively weak model in forecasting major events in New Zealand, California, Japan and Greece shows that the predictive scaling relations are ubiquitous in earthquake catalogues. Although none of the formal tests of the swarm hypothesis were successful in their own terms, they were beneficial in identifying shortcomings in its formulation, thereby leading to improved understanding of long-term seismogenesis and a better forecasting model. Some puzzling aspects of the scaling relations are whether they vary regionally, and why the precursor area and aftershock area scale differently with magnitude. A more practical question is whether the EEPAS model can be strengthened, by making use of the clustering of some precursors in swarms and quarms, to bring us nearer to the original goal of forecasting individual major earthquakes.     

中国渤海地区海底地震观测的初步研究

本文是在日本造船振兴财团的经费赞助下在中国渤海地区发展海底地震观测的初步技术报告。本报告主要包括以下内容: (1) 渤海及其邻近地区的地震活动性与地震危险性估计; (2) 渤海地区海底地震观测的条件; (3) 渤海地区海底地震观测仪器与技术的某些初步研究结果; (4) 浅海情况下海底地震观测噪声的模拟实验研究结果。文中研究了该地区的历史与现代地震活动性、长期地震危险性以及发生在华北与日本的大地震之间的关系。还讨论了渤海强震和海啸对渤海及其邻近海域航海的影响问题。在这些研究结果的基础上对在渤海地区开展海底地震观测的必要性进行了解释。本文探讨了在渤海地区进行海底地震观测的某些仪器和技术问题。天津市地震局曾在渤海地区石油平台的油井中作过初步地震观测试验。日本气象厅气象研究所发展的海底地震观测中有关降低噪声与信号传输等方面的新技术与经验可用于渤海地区的海底地震观测。在这些研究的基础上,提出了一个在中国渤海地区发展渤海地震观测的初步设想。指出渤海海底地震观测试验应从观测和研究渤海海底海洋噪声谱开始。为了研究浅海情况下海底地震观测的噪声,本文完成了一项新的模拟试验工作。分别对海面源及海内源产生的噪声进行了实验研究。文中给出了一些重要实验结果。本文所得的初步结果,对发展渤海及邻近地区海底地震观测有一定的参考价值。     

Intelligent seismic isolation system using air bearings and earthquake early warning

Recently strong seismic waves or long period seismic waves have been observed in various earthquakes that occurred in Japan. As a result improvements of existing seismic isolation systems are deemed necessary. The present study proposed an intelligent seismic isolation system encompassing air bearings and earthquake early warning (EEW) system. Such system exhibits adequate isolation performance. The air bearings are isolation device that may render infinite the superstructure natural period by floating them, and the EEW is applied for a trigger of isolation. This paper illustrates the proposed system and discusses the experimental results of a test carried out with the system. Laboratory tests carried out in the present research demonstrate the effectiveness of the proposed base isolated systems and prove its efficacy in mitigating the effects of three-dimensional seismic waves. For example, the system suppressed the horizontal response acceleration of an isolation target to 38% of input acceleration.     

烟囱模型动力试验研究

烟囱结构的地震反应及其破坏机理是地震工程界长期讨论的问题，对高耸烟囱结构的模型试验研究是研究此工程问题的重要方法，作者通过对45m和180m高大烟囱结构的动力模型试验，对烟囱结构的地震反应及其破坏机理进行了模型试验研究，得出了有意义的结论，为这一问题的理论研究提供了有力的依据。     

地基抗液化能力评估方法讨论

为了评估地基抵抗液化的能力及其影响因素,本文介绍了标准贯入试验、静力触探试验以及剪切波速试验三种评估地基抗液化能力方法的研究成果,分析了震级比例系数、覆盖压力与倾斜地面的修正系数、地震震级与峰值加速度的影响,并对地基抗液化能力的概率分析方法进行了讨论,得到的结论可为地基的抗液化能力评估提供参考。     

Transient analysis of 1D inhomogeneous media by dynamic inhomogeneous finite element method

The dynamic inhomogeneous finite element method is studied for use in the transient analysis of one dimensional inhomogeneous media. The general formula of the inhomogeneous consistent mass matrix is established based on the shape function. In order to research the advantages of this method, it is compared with the general finite element method. A linear bar element is chosen for the discretization tests of material parameters with two fictitious distributions. And, a numerical example is solved to observe the differences in the results between these two methods. Some characteristics of the dynamic inhomogeneous finite element method that demonstrate its advantages are obtained through comparison with the general finite element method. It is found that the method can be used to solve elastic wave motion problems with a large element scale and a large number of iteration steps.     

日本1995年阪神大地震及火山考察与启示

简述了１９９５年１月１７日日本７．２级阪神大地震的震害,地震断层以及１８９１年浓尾级地震根尾谷地震断裂、北伊豆地震旦那断层和大室火山、伊豆大岛火山的一些特征,最后论述了这次考察的启示。     

近海地震活动特征及其测震学前兆的某些研究

利用反映震级－频度关系的参量Ｃ值，η值，ｂ值和ｂ值谱以及反映地震空间分布的森下指等研究了近海地震活动的一些主要特征，发现近海强震前地震活动性指标及图象的变化特征与陆地上强震前的特征存在一定差异；给出了新研究的可用于近海及滨海地区强震预报的短期和临震