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为进一步加深对大容量气枪震源激发的地震波传播特性的认知,利用福建海陆多个气枪震源固定激发点重复激发的实验数据,通过线性叠加和仿真技术得到等效单次激发高信噪比速度和位移记录,然后利用不同震中距的位移峰值计算不同固定点气枪激发的等效震级,进而建立等效震级、震中距和速度峰值的衰减关系。结果表明:(1)震中距为0~270km时,大容量气枪单次激发得到的速度峰值为700~4nm/s,位移峰值为200~0.2nm;(2)总容量为8000 in~3的气枪震源P波等效震级为0.181~0.760,S波等效震级为0.294~0.832,总容量为12000 in~3的气枪震源P波等效震级为0.533~0.896,S波等效震级为0.611~0.946,气枪震源激发产生的S波能量大于P波能量,激发环境不同,激发效能相差较大;(3)速度峰值随等效震级增大而增大,随震中距增大而减小,P波速度峰值三分量中垂直分量最大,S波相反,其垂直分量最小,二者水平分量相近。研究结果可为定量判断气枪震源激发的地震波的传播能力以及利用气枪震源进行深部探测或监测的观测系统的设计提供重要依据。 相似文献
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利用山东数字地震台网二年多的地震记录资料,根据陈培善等用地震发生的断裂力学模式和震源谱理论,导出的震源处峰值加速度与构造环境剪应力值的关系,计算了山东内陆及附近海域发生的46次中小地震构造环境剪应力值,并对应力场的分布状况和时空变化进行了分析。 相似文献
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在场地波速测量中,由于噪声等因素的影响很难准确识别P、S波的初至时刻,致使波速结果存在很大的误差。本文给出了一种基于小波变换的波速测量的新方法。该方法利用波动信号的小波变换与弹性波群速度的关系准确识别弹性波初至时刻。弹性波小波变换的峰值时刻代表着以群速度传播的弹性波的初至时刻,使P波、S波的初至时刻的确定具有明确的物理意义,波速的结果准确、可靠、稳定。此外,波动信号的小波多尺度分析还可以确定地层中传播的弹性波的频散特性。最后,该方法在场地波速测量的实测信号的应用表明该方法可准确确定P、S波速。 相似文献
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In this article, the seismic records of Japan’s Kik-net are selected to measure the acceleration, displacement, and effective peak acceleration of each seismic record within a certain time after P wave, then a continuous estimation is given on earthquake early warning magnitude through statistical analysis method, and Wenchuan earthquake record is utilized to check the method. The results show that the reliability of earthquake early warning magnitude continuously increases with the increase of the seismic information, the biggest residual happens if the acceleration is adopted to fit earthquake magnitude, which may be caused by rich high-frequency components and large dispersion of peak value in acceleration record, the influence caused by the high-frequency components can be effectively reduced if the effective peak acceleration and peak displacement is adopted, it is estimated that the dispersion of earthquake magnitude obviously reduces, but it is easy for peak displacement to be affected by long-period drifting. In various components, the residual enlargement phenomenon at vertical direction is almost unobvious, thus it is recommended in this article that the effective peak acceleration at vertical direction is preferred to estimate earthquake early warning magnitude. Through adopting Wenchuan strong earthquake record to check the method mentioned in this article, it is found that this method can be used to quickly, stably, and accurately estimate the early warning magnitude of this earthquake, which shows that this method is completely applicable for earthquake early warning. 相似文献
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中国古建筑抗震性能分析 总被引:8,自引:4,他引:4
本文根据我国古建筑在历次地震作用下的结构破坏状况,总结了古建筑结构的震害特点,介绍了古建筑抗震性能分析方法,结合泰安市古建筑实例进行了抗震性能分析并给出了抗震性能分析结果。 相似文献
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利用概率地震危险性分析(CPSHA)方法,对山东某场地进行地震危险性分析,通过对该场地划分潜在震源区,确定地震活动性参数及地震动衰减关系,计算分析地震危险性概率,基本确定对该场地地震动峰值加速度起主要贡献的几个潜在震源区及贡献值,并确定该场地50年超越概率10%的水平向基岩地震动加速度峰值。结果发现,CPSHA方法以具体的构造尺度和更加细致的构造标志来划分潜在震源区,使潜在震源区规模缩减,从而更能反映地震活动在空间分布上的不均匀性。 相似文献
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本文基于笔者采用过的同时考虑房屋层数和场地类别时烈度到水平向地面峰值转换的基本思路,统计研究了烈度与竖向地面峰值的对应关系,明确指出了不同烈度下竖向与水平向峰值的比值应该是有所不同的,并给出了建议的比值,给果可供一般工程抗震设计参考使用。 相似文献
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中国大陆强震前兆时空分布的大尺度特征初探 总被引:4,自引:3,他引:1
依据对中国大陆一些强震(M_s≥7.0)震例前兆异常的分析,初步阐述了中国大陆强震前兆时空分布的大尺度特征:①强震的前兆场及震后的影响场是广阔的;②有些前兆异常的时间较长,可能与几个强震有关,持续十几年。 相似文献
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A wide variety of near-fault strong ground motion records were collected from various tectonic environments worldwide and were used to study the peak value ratio and response spectrum ratio of the vertical to horizontal component of ground motion, focusing on the effect of earthquake magnitude, site conditions, pulse duration, and statistical component. The results show that both the peak value ratio and response spectrum ratio are larger than the 2/3 value prescribed in existing seismic codes, and the relationship between the vertical and horizontal ground motions is comparatively intricate. In addition, the effect of the near-fault ground motions on bridge performance is analyzed, considering both the material nonlinear characteristics and the P~? effect. 相似文献
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以美国加州强震观测计划(CSMIP)的6个土工台阵和日本Hosokura矿台阵为研究对象, 以323组三分量地表和地下地震动峰值数据为基础, 按照台阵场地的软硬和土层分布, 将其分为基岩、 土层和ldquo;土层/基岩rdquo;台阵. 对于同一类台阵记录的所有地震, 分别按照震级和地表地震动峰值的大小将其分类. 对于同一类台阵的各类地震, 分别对加速度、 速度和位移峰值沿深度的变化进行统计分析, 得到沿深度变化的峰值比, 并且用非线性最小平方法, 采用指数衰减模型, 对峰值比沿深度变化曲线进行拟合. 通过对各类场地的各类地震的分析, 得到了地震动峰值沿深度变化的初步规律. 相似文献
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李永振 《地震地磁观测与研究》2011,32(2):42-46
2008年辽宁海城M 4.3地震,辽宁省强震动台网12个强震台站记录到地面运动,是辽宁省自开展强震动观测以来同时获取强震记录最多的一次,记录的最大加速度为167.5 cm·s-2,初步展现了辽宁省强震动台网建设的成效. 相似文献
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李永振 《地震地磁观测与研究》2011,32(6):42-46
2009年吉林伊通M4.3地震,辽宁省及吉林省强震动台网有8个强震台站记录到地面运动,记录的最大加速度为30.8 cm·s-2,初步展现了强震动台网建设的功效. 相似文献
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Generating ground motion by two new techniques of adding harmonic wave in the time domain and approximating to response spectrum as a whole 总被引:2,自引:0,他引:2
GeneratinggroundmotionbytwonewtechniquesofaddingharmonicwaveinthetimedomainandapproximatingtoresponsespectrumasawholeCHANG... 相似文献
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Peak velocities and peak surface strains during Northridge, California, earthquake of 17 January 1994 总被引:1,自引:0,他引:1
M.D. Trifunac M.I. Todorovska S.S. Ivanovi? 《Soil Dynamics and Earthquake Engineering》1996,15(5):301-310
We present contours of the largest horizontal and vertical recorded peak velocities of strong ground motion during the Northridge, California, earthquake. Above the fault, the horizontal peak velocities exceeded 100 cm/s. The vertical velocities were larger than 20 cm/s. We also present contours of peak horizontal and vertical strain factors. Through most of the San Fernando Valley and the Santa Susana Mountains, the horizontal surface strain factor was larger than 10−3. The largest horizontal strain factor computed was for the Rinaldi Receiving Station ∼10−2·2. The corresponding vertical strains were >10−3·25 and 10−13, respectively. Through most of the Los Angeles Basin the horizontal peak surface strain factors were between 10−3·75 and 10−3. 相似文献