【作者】 刘培玄；

【导师】 周正华；

【作者基本信息】 中国地震局工程力学研究所 ， 防灾减灾工程及防护工程， 2012， 硕士

【摘要】 长周期地震动衰减关系统计分析及地震动衰减特征影响因素的研究是近年来地震工程领域中的主要研究课题。本文以新西兰克莱斯特彻奇市附近的两次地震的强震动记录及川滇地区的26次破坏性地震的强震动记录为基础数据，围绕地震动衰减特征分析中的关键问题—长周期地震动衰减关系建立、震源深度对地震动衰减特征的影响进行了深入分析，主要开展的相关工作如下：1.概括介绍了长周期地震动衰减关系研究现状及其相关研究成果，指出了现有相关研究中存在的问题，并阐明了开展长周期地震动衰减特性研究的必要性。2.基于地震动加速度基线校正方法，峰值加速度、加速度反应谱、累积绝对速度计算方法，以及最小二乘法的两步回归分析；以新西兰克莱斯特彻奇市附近的两次地震的强震动加速度记录为基础数据，进行了相应的计算和回归分析，得到了竖向与水平向峰值加速度比的分布，并建立了峰值加速度、4个周期点的加速度反应谱、累积绝对速度等地震动参数的衰减关系，讨论了震源深度对峰值加速度比和地震动参数衰减特征的影响。同时，通过对莱斯特彻奇市附近6个典型场点的地震动加速度反应谱对比分析，进一步讨论了震源深度对加速度反应谱的影响。另外，依据两次地震的地震动特征差异，讨论了两次地震的震害迥异的原因。3.介绍了合成人造地震动的方法、一维土层地震反应分析的等效线性化方法及不同场地条件下的6个实际工程场地分析模型，并进行了人造地震动时程的合成和土层水平向地震反应的计算，对比分析了基岩场地和不同土层场地自由地表加速度反应谱，讨论了场地覆盖层厚度对长周期地震动的影响，并通过对比分析汶川地震主震强震动记录反应谱进一步验证了数值模拟结果所得结论。4.通过典型场地的数值模拟及实际地震记录分析，讨论了将土层场地上的强震动记录直接应用于基岩场地上的长周期地震动加速度反应谱衰减关系回归统计分析的适用条件。5.以满足筛选条件的强震动加速度记录为基础数据，基于最小二乘法的两步回归分析，建立了基岩场地上8-15s内6个周期点的加速度反应谱衰减关系，并通过随震级、距离的变化分析，及与实际地震记录的对比，讨论了衰减关系回归统计结果的合理性。6.对全文的研究工作进行了总结，并提出了本文有待进一步研究的工作。更多还原

【Abstract】 In recent years, the statistical analysis of attenuation relationship of longperiod ground motion and the study on the influencing factors of seismicattenuation characteristics are the major research subjects in earthquakeengineering. Based on the records from2earthquakes occurred in theChristchurch region and26destructive earthquakes occurred in Sichuan-Yunnanregion, the key problems in the characteristics analysis of ground motionattenuation, the attenuation relationship establishment of long period groundmotion and effect of hypocenter depth on the ground motion attenuationcharacteristics, are deeply analyzed. The main contents are as following:1. The research status for the attenuation relationship of long period groundmotion and the relevant research results are generally introduced. According tothe recent study, some problems still remain unsolved. The reason why it’snecessary to carry on this research is explained.2. Based on the records from2earthquakes occurred in the Christchurchregion, by using the acceleration baseline correction method, the calculationmethod of peak ground acceleration, the acceleration response spectra and thecumulative absolute velocity and the2steps regressing least square method, thecorresponding calculation and regression analysis is done to analyze the peakground acceleration, the acceleration response spectra and the cumulativeabsolute velocity. The distribution of ratio of vertical to horizontal ground motionacceleration is got. The attenuation relationships of the peak ground acceleration,acceleration response spectra at4period points and cumulative absolute velocityare established. The effect of hypocenter depth on the peak ground accelerationratio and attenuation characteristics of ground motion parameters is discussed.The acceleration respongse spectra at6typical sites of Christchurch region arecompared to further study the effect of the hypocenter depth on the accelerationresponse spectra. According to the different characteristics of ground motion, theearthquake damage difference in2earthquakes is analyzed.3. The artificial ground motion generation method and one-dimensionequivalent linear method of seismic responses for soil layers are introduced. Theground motion response of6calculation models with different site conditionsunder the input of artificial ground motion is calculated. The response spectra onthe free surface and bedrock are compared to discuss the effect of soil layerthickness on the long period ground motion. By compared with the strong motionrecords on different site condition from Wen Chuan earthquake, the numericalsimulation results are verified.4. Based on the numerical simulation of the typical sites and the analysis ofaccelerogram from Wenchuan earthquake, the applying conditions of which thestrong motion accelerograms on the soil layer sites are used directly to theStatistical regression analysis of the attenuation relationship of long period acceleration response spectra on the bedrock site, are discussed.5. Based on the strong motion acceleration records meeting the screeningconditions, the2steps regressing least square method is used to establish theattenuation relationship of acceleration response spectra at6periods from8to15second. By comparing the change of attenuation relationship with the magnitudeand distance and the actual earthquake records, the regression statistic rationalityof attenuation relationship is discussed.6. The study work in this paper is summarized, and the following work to bestudied further is put forward.更多还原