| 地震动强度对斜坡加速度动力响应规律的影响 |
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| 引用本文： | 刘汉香,许强,范宣梅,徐鸿彪.地震动强度对斜坡加速度动力响应规律的影响[J].岩土力学,2012,33(5):1357-1365. |
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| 作者姓名： | 刘汉香 许强 范宣梅 徐鸿彪 |
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| 作者单位： | 1.成都理工大学 地质灾害防治与地质环境保护国家重点实验室，成都 610059； 2.四川省交通运输厅公路规划勘察设计研究院，成都 610041 |
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| 基金项目： | 国家重点基础研究发展计划(973计划)资助项目(No.2008CB425801);教育部创新团队发展计划(No.IRT0812);地质灾害防治与地质环境保护国家重点实验室自主研究课题“汶川地震大型滑坡研究” |
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| 摘 要： | 依托大型振动台试验成果，采用加速度响应峰值PGA及其放大系数相结合的分析方法，系统地探讨了上硬、下软和上软、下硬两种岩性组合结构斜坡模型，分别在正弦波和天然地震波作用下坡面各高程点的水平向和竖直向加速度响应随震动强度增大的变化规律。试验结果分析表明：①在天然波作用下两斜坡模型的水平向和竖直向PGA均随震动强度增大而增大，而放大系数则随震动强度增大到一定程度时，逐渐减小并趋于稳定；②在正弦波作用下两斜坡模型的水平向和竖直向PGA亦随震动强度增大而增大，然而竖直向PGA放大系数随震动强度增大亦有所增大，说明竖直向加速度响应表现出了相对于水平向响应较弱的非线性特征；③在水平向和竖直向地震力作用下加速度响应沿高程表现出的放大效应分别体现在斜坡模型的上段和下段。此外，斜坡模型的加速度响应沿坡面在坡脚、坡中和坡肩等特殊部位出现了多个极值区；④在水平向地震力作用下低频的地震波作用要强于高频地震波，且加速度在上硬、下软岩性组合结构斜坡模型中的响应要强于上软、下硬岩性组合斜坡模型；在竖直向地震力作用下则呈现相反结果。其研究结果对高地震风险山区的防震减灾及灾后重建都具有指导和借鉴意义。
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| 关 键 词： | 斜坡 地震动强度 正弦波 天然地震波 加速度响应峰值 放大系数 |
| 收稿时间： | 2010-11-16 |
Influence of ground motion intensity on dynamic response laws of slope accelerations |
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| LIU Han-xiang
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XU Qiang
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FAN Xuan-mei
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XU Hong-biao.Influence of ground motion intensity on dynamic response laws of slope accelerations[J].Rock and Soil Mechanics,2012,33(5):1357-1365. |
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| Authors: | LIU Han-xiang XU Qiang FAN Xuan-mei XU Hong-biao |
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| Institution: | 1.State Key Laboratory of Geohazard Prevention and Geoenvironment Protection, Chengdu University of Technology, Chengdu 610059, China; 2.Sichuan Provincial Transport Department Highway Planning, Survey, Design and Research Institute, Chengdu 610041, China |
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| Abstract: | Based on large-scale shaking table tests,using the pre-processed peak ground acceleration(PGA) and its amplification factor,taking slopes with two types of lithology variations including high strength materials overlying low strength materials and low strength materials overlying high strength materials as the research objects,this paper investigates systematically the change laws of the horizontal and vertical accelerations in different slope levels with the gradual increasing intensity,under sine waves and crude seismic waves.Analysis shows that: ① When crude seismic waves are loaded,the PGAs in two directions both increased as input waves strengthened,while their corresponding amplification factors increased first,then gradually decreased into stability change.② When sine waves are loaded,the PGAs in two directions also increased as input waves strengthened,however,their corresponding amplification factors still increased slowly all the time,which indicates the weaker nonlinearity.③ Under the horizontal and vertical seismic action of the same magnitude,the acceleration amplification appears respectively in the upper part and in the lower part of the two slope models.In addition,several extremum zones of accelerations appear at the bottom,middle and top of slope models.④ Under the horizontal seismic action,the effect of low frequency is stronger than that of high frequency,furthermore,with the same seismic wave,the acceleration responses in slope with high strength materials overlying low strength materials are stronger than those in the other slope;while under the vertical seismic action of the same magnitude,the results are contrary.The research provides a guidance and reference to quakeproof and post-disaster reconstruction in the high seismic hazard zones. |
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| Keywords: | slope ground motion intensity sine wave crude seismic wave peak ground acceleration amplification factor |
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