Effects of site conditions on earthquake ground motion and their applications in seismic design in loess region
Effects of site conditions on earthquake ground motion and their applications in seismic design in loess region
复制标题
场地条件对地震动的影响及其在黄土地区抗震设计中的应用
DOI：
10.1007/s11629-016-3921-7
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发表时间：
2017-06-01
影响因子：
2.5
通讯作者：
Xia, Kun
中科院分区：
文献类型：
--
作者：
Wang, Lan-min;Wu, Zhi-jian;Xia, Kun
黄土高原是我国的地震多发区，在2008年汶川8. 0级地震和2013年岷县-漳县6. 6级地震中发现了黄土存款对地震动的影响。现场调查、观测和分析表明，地震不仅造成了大量人员伤亡和巨大经济损失，而且还受到场地条件、地形地貌、黄土存款厚度等因素对地震动的放大作用。本文选取大寨村和马家沟村作为两次地震影响的典型黄土场地，进行了烈度评估、钻孔勘探、临时强震台阵、微动测量和数值分析。目的是探讨放大因子与地形、黄土存款厚度等场地条件的关系。我们还开发了场地地面运动放大系数的工程设计考虑在黄土网站。结果表明，随着黄土存款厚度的增加和坡高的增加，放大效应更加显著。放大作用可使地震烈度增加1度，PGA和卓越周期分别增加2倍。
The Loess Plateau is an earthquake prone region of China, where the effects of loess deposit on ground motion were discovered during the 2008 Wenchuan earthquake (Ms8.0) and the 2013 Minxian-Zhangxian earthquake (Ms6.6). The field investigations, observations, and analyses indicated that large number of casualties and tremendous economic losses were caused not only by collapse and damage of houses with poor seismic performance, landslides, but also amplification effects of site conditions, topography and thickness of loess deposit, on ground motion. In this paper, we chose Dazhai Village and Majiagou Village as the typical loess site affected by the two earthquakes for intensity evaluation, borehole exploration, temporary strong motion array, micro tremor survey, and numerical analysis. The aim is to explore the relations between amplification factors and site conditions in terms of topography and thickness of loess deposit. We also developed site amplification factors of ground motion for engineering design consideration at loess sites. The results showed that the amplification effects are more predominant with increase in thickness of loess deposit and slope height. The amplification may increase seismic intensity by 1 degree, PGA and predominant period by 2 times, respectively.