| 引用本文: | 胡进军,章文波,谢礼立.震源深度对地震动方向性特征的影响[J].哈尔滨工业大学学报,2014,46(10):94.DOI:10.11918/j.issn.0367-6234.2014.10.016 |
| HU Jinjun,ZHANG Wenbo,XIE Lili.Effect of fault depth on directivity of ground motions[J].Journal of Harbin Institute of Technology,2014,46(10):94.DOI:10.11918/j.issn.0367-6234.2014.10.016 |
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| 摘要: |
| 为了定量分析地震震源深度对近断层地震动及其在地表的空间展布特征的影响,本文采用一个典型的走滑地震震源模型,基于离散波数有限元方法计算了5种不同震源深度工况下的地震动及其分布场,对地震动幅值、频谱和持时的方向性特征进行分析,结果表明：随着震源深度的增加,地震动的幅值降低,并且在破裂前方和破裂后方存在明显差异；震源深度不同,地震动的空间分布特征也不同；在地震动场中存在一个明显受到方向性效应影响和控制的区域,此区域的位置和面积随着震源深度变化而改变；在地震工程中预测地震动时,特别是当工程中需要考虑地震的近场效应时,震源深度参数是一个不可忽略的因素. |
| 关键词: 地震动 数值模拟 震源深度 影响区域 |
| DOI：10.11918/j.issn.0367-6234.2014.10.016 |
| 分类号:P315.3 |
| 基金项目:国家国际科技合作专项资助项目(2012DFA70810)；国家自然科学基金资助项目(2,1)；黑龙江省青年科学基金资助项目(QC2011C058). |
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| Effect of fault depth on directivity of ground motions |
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HU Jinjun1,2, ZHANG Wenbo2, XIE Lili1,3
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(1. Key Laboratory of Earthquake Engineering and Engineering Vibration,Institute of Engineering Mechanics, China Earthquake Administration, 150080 Harbin, China; 2. College of Earth Science, University of Chinese Academy of Sciences, 100049 Beijing, China; 3. School of Civil Engineering, Harbin Institute of Technology, 150090 Harbin, China)
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| Abstract: |
| Earthquake source parameters have important impact on the near-fault ground motions and their spatial distribution characteristics. Using a discrete wavenumber finite element method, we simulate the ground motion fields, and then study the effect of fault depth on ground motion amplitude, spectra and duration from the directivity point of view. Numerical results show that: with increasing fault depths, the amplitude decreases but the difference between forward and backward direction still exists; the significantly affected areas is getting closer to the fault; and the radiation angle of directivity effect gradually extends to both sides of the fault strike. This phenomenon indicates that the source depth not only affect the amplitude of ground motion but also the significantly affected areas and locations. Therefore, the source depth parameter should be considered in the prediction of ground motion in engineering, especially in near-fault region. |
| Key words: ground motion numerical simulation fault depth affected areas |
