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1.
范家参  费维水 《地震研究》1996,19(1):95-118
本文用具有非线性Rayleigh阻尼的断裂动力学的控制方程组或方程来研究水平强震地面运动或垂直强震地面运动,并得出其解析解,数值计算结果显示,本文得出的结果与任意选择的两个强震记录是很相似的。  相似文献   

2.
本文描述强震地面运动持续时间的几个经验模型。我们将运动函数f(t)的持续时间定义和积分∫^10f^2(τ)dτ达到其最终数值的重要部分的时间间隔的总和。此外f(t)为加速速度、速度或位移。所有记录均通过12个窄滤波器进行带通滤波,而强震地面运动的持续时间系在这些频带分别进行研究。除子震级、震中距等传统参数之外,还考虑其他三个参数,这些参描述围绕着记录台站的沉积盆地的几何形状。文中说明沉积物的存在怎  相似文献   

3.
地震是活动断裂构造在区域构造应力场作用下,应变能释放的结果。地表建筑,构筑物的地震破坏与地震形变带均匀为同一构造应力场作用的产物,所以它们必然具有相同的力学性状特征。本文通过国内外一些强烈地震震害实例,充分论主下了地震地面运动卓越方向的存在,并指出了它在抗震防灾及工程抗震和震害预测预防方面的重要性。  相似文献   

4.
利用高频GPS技术进行强震地面运动监测的研究进展   总被引:7,自引:0,他引:7       下载免费PDF全文
回顾了高频(1 Hz) GPS在地学应用中的研究进展和主要的数据处理方法,全面比较了高频GPS与地震仪的工作原理与性能,认为高频GPS可为后者进行有效的补充;分析了高频GPS应用于监测短周期强震地面运动的技术优势,以及在处理方法和实际的地学应用中存在的不足;通过对高频GPS的应用领域与发展前景的研究,对我国开展高频GPS数据的处理方法与地学应用研究提出了自己的观点和看法.  相似文献   

5.
施甸地震强震观测记录及其初步分析   总被引:3,自引:1,他引:3  
在2001年4月12日发生的施甸5.9级地震中,依据地震预报意见布设在滇西的短临跟踪临时强震台网获取了该次地震的强地面运动记录,最大加速度峰值达515gal(未校正),获取大于500gal主震记录,这在我国还是首次,对记录的情况作了简要的介绍。  相似文献   

6.
由于新规定要求危险性估计必须使用概率术语,进行概率危险性研究的数量最近一直在增加。本研究旨在确定根据这些研究和观测进行比较预测的可能性和范围。直接根据地面运动发生率的比较检验比地震发生率更受青睐。根据泊松过程的特性,计算和评估了能确保场点发生率估计可靠的最小时间窗。例如,对于场点复发期为475年的地面运动,要求用来估计地面运动发生率的最小观测时间窗为12000年,且不确定性为20%(变异系数:标准差除以平均值)。这些值不取决于所研究地区的地震活动性水平。对法国固定加速度计台网台站记录的地面运动进行的分析表明,对于很低的加速度水平(STET台站0.0001~0.001g),地面运动发生率估计的最高精确度为30%。在有更长记录历史和位于更高地震活动区(希腊和加利福尼亚州)的2个台站进行的同样分析,提供了可达0.1g的地面运动水平。因此,提出的问题是,即使使用的是对于广泛范围的加速度都一致有效的地面运动预测公式,基于低加速度水平的比较检验所得出的结果能推广到更高的加速度水平吗?  相似文献   

7.
地震危险性概率分析(PSHA)是目前最广泛应用于地震灾害与风险性评估的方法。然而它在计算中却存在着一个错误:把强地面运动衰减关系(一个函数)的条件超越概率等同于强地面运动误差(一个变量)的超越概率。这个错误导致了运用强地面运动误差(空间分布特征)去外推强地面运动的发生(时间分布特征)或称之为遍历性假设,同时也造成了对PSHA理解和应用上的困难。本文推导出新的灾害计算方法(称之为KY-PSHA)来纠正这种错误。  相似文献   

8.
简要总结了近年来我国在强地面运动资料的处理、近断层地面运动的影响因素、强地面运动的模拟和宽频带反应谱等方面的研究工作.同时,回顾与展望了我国在强地面运动研究方面的国际合作进展.   相似文献   

9.
杜春清  李锰 《内陆地震》2009,23(4):444-449
根据新疆喀什地区两次地震中新疆强震台网记录的加速度数据,分析介绍了强震观测资料的常规处理和使用,并简介了强震观测资料在研究地面运动特征中的作用。  相似文献   

10.
引言虽然我们能够使用不同的正演模拟技术成功地模拟低频地面运动,但使用目前的计算技术和关于地球结构知识对3~5Hz以上频率地面反应的确定性模拟仍是一个未能解决的课题。最近,我们在多源模型(Tumarkin and Archuleta,1994)的基础上发展了一种地面运动预测的经验方法。利用多种经验格林函数方法的思路都是利  相似文献   

11.
This paper presents a review of the advances in strong motion recording since the early 1930s, based mostly on the experiences in the United States. A particular emphasis is placed on the amplitude and spatial resolution of recording, which both must be ‘adequate’ to capture the nature of strong earthquake ground motion and response of structures. The first strong motion accelerographs had optical recording system, dynamic range of about 50 dB and useful life longer than 30 years. Digital strong motion accelerographs started to become available in the late 1970s. Their dynamic range has been increasing progressively, and at present is about 135 dB. Most models have had useful life shorter than 5–10 years. One benefit from a high dynamic range is early trigger and anticipated ability to compute permanent displacements. Another benefit is higher sensitivity and hence a possibility to record smaller amplitude motions (aftershocks, smaller local earthquakes and distant large earthquakes), which would augment significantly the strong motion databases. The present trend of upgrading existing and adding new stations with high dynamic range accelerographs has lead to deployment of relatively small number of new stations (the new high dynamic range digital instruments are 2–3 times more expensive than the old analog instruments or new digital instruments with dynamic range of 60 dB or less). Consequently, the spatial resolution of recording, both of ground motion and structural response, has increased only slowly during the past 20 years, by at most a factor of two. A major (and necessary) future increase in the spatial resolution of recording will require orders of magnitude larger funding, for purchase of new instruments, their maintenance, and for data retrieval, processing, management and dissemination. This will become possible only with an order of magnitude cheaper and ‘maintenance-free’ strong motion accelerographs. In view of the rapid growth of computer technology this does not seem to be (and should not be) out of our reach.  相似文献   

12.
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   

13.
2009年2~4月,柯坪块体先后发生了3次5级地震。新疆地震局布设在南天山西段数字强震动台网获取了这3次地震的主震加速度记录。文中对3次地震加速度记录进行了常规数据处理。按地震动三要素计算了地震烈度,并将计算的烈度与地震宏观考察烈度进行了比较。  相似文献   

14.
唐山丰南M4.1级地震强震记录分析   总被引:3,自引:2,他引:1  
2010年4月9日唐山丰南发生M4.1级地震,津冀地区共有36个强震台站获取到强震记录,记录的最大加速度为58.92cm/s2,通过对比强震记录的峰值,发现该地震竖向峰值比水平向大,在三个分量上加速度傅氏谱谱型以多峰为主。通过对强震记录频谱特征进行分析,得出随着震中距的增大,反应谱高频成分衰减快于低频成分,竖向与水平向加速度比值与常规认为的1/2—2/3差别较大。通过对本次强震动记录反应谱标定并结合唐山地区3.5级以上地震记录,获得唐山地区土层场地反应谱谱型参数。  相似文献   

15.
A note on the useable dynamic range of accelerographs recording translation   总被引:2,自引:0,他引:2  
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   

16.
Effect of tilt on strong motion data processing   总被引:5,自引:2,他引:5  
In the near-field of an earthquake the effects of the rotational components of ground motion may not be negligible compared to the effects of translational motions. Analyses of the equations of motion of horizontal and vertical pendulums show that horizontal sensors are sensitive not only to translational motion but also to tilts. Ignoring this tilt sensitivity may produce unreliable results, especially in calculations of permanent displacements and long-period calculations. In contrast to horizontal sensors, vertical sensors do not have these limitations, since they are less sensitive to tilts. In general, only six-component systems measuring rotations and accelerations, or three-component systems similar to systems used in inertial navigation assuring purely translational motion of accelerometers can be used to calculate residual displacements.  相似文献   

17.
In Ms7.0 Lushan earthquake, a large amount of strong ground motion recordings were collected. In this paper, we analyze the recordings carefully. The abnor- mality of ground motion recordings is identified through a log linear regression. In the station of 51BXD, the PGA value has exceeded 1 g, which is the biggest peak ground acceleration (PGA) value obtained from all recordings in this earthquake. The log linear relation shows the PGA value in this station is abnormally large. As this station is located on the footage of a hill, the topographic amplifi- cation factor is explored in order to explain this abnor- mality. Through 3D numerical modeling using spectral element method with transmitting boundary conditions, the amplification factor is quantized. In this station, the topo- graphic amplification is highly polarized in the direction of East-West which agrees with the empirical recordings. This research result suggests us in future directionality of topographic amplification should be considered in the aseismic design.  相似文献   

18.
安徽强震动台站场地响应研究   总被引:1,自引:0,他引:1  
采用H/V谱比法,利用安徽强震台网记录的波形数据,计算了3个强震台的场地响应。结果表明,当台站场地为基岩或覆盖层较薄时,由地脉动和S波数据分别计算出的谱比曲线一致性很好。当覆盖层大于30.5 m的时候,两者的放大因子有差异,即用S波计算的场地放大响应要明显大于用脉动计算的场地响应。  相似文献   

19.
2013年6月2日台湾南投地震强地面运动模拟   总被引:1,自引:0,他引:1       下载免费PDF全文
2013年6月2日台湾省南投县发生一次里氏6.5级地震,这次地震是最近几年内发生的最大的一次地震,台湾大部分地区以及中国大陆东南沿海城市均有明显震感.为了更深入的理解此次地震的地震波能量传播过程以及强地面运动过程,本文采用三维有限差分方法对此次地震的强地面运动过程进行了模拟.结果显示,台湾中央山脉起伏的地形对此次地震的强地面运动分布特征具有较大的影响,出现了比较明显的地形放大效应;此外,台湾的平原和盆地中的沉积层也对地震波有较强的放大效应.  相似文献   

20.
Turkey was struck by two major events on August 17th and November 12th, 1999. Named Kocaeli (Mw=7.4) and Düzce (Mw=7.2) earthquakes, respectively, the two earthquakes provided the most extensive strong ground motion data set ever recorded in Turkey. The strong motion stations operated by the General Directorate of Disaster Affairs, the Kandilli Observatory and Earthquake Research Institute of Bogazici University and Istanbul Technical University have produced at least 27 strong motion records for the Kocaeli earthquake within 200 km of the fault. Kocaeli earthquake has generated six motions within 20 km of the fault adding significantly to the near-field database of ground motions for Mw>=7.0 strike–slip earthquakes. The paper discusses available strong motion data, studies their attenuation characteristics, analyses time domain, as well as spectral properties such as spectral accelerations with special emphasis on fault normal and fault parallel components and the elastic attenuation parameter, kappa. A simulation of the Kocaeli earthquake using code FINSIM is also presented.  相似文献   

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