非饱和土成层场地波动问题的解析解及应用

李伟华; 胡叶尘; 赵成刚; 郑洁

doi:10.11779/CJGE201810005

非饱和土成层场地波动问题的解析解及应用 English Version

1. 北京交通大学土木建筑工程学院,北京 100044;
2. 上海朗信房地产开发有限公司,上海 201306;
3. 中冶京诚工程技术有限公司,北京 100176

基金项目: 国家自然科学基金项目（51378058）; 国家重点基础研究发展计划项目（2015CB057800）; 中央高校基本科研业务费专项（2015JBZ008）

详细信息

作者简介:
李伟华（1976- ）女,博士,副教授,主要从事土动力学和地震工程方面的研究。E-mail：whli@bjtu.edu.cn。

中图分类号: TU43
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出版历程
- 收稿日期: 2017-07-30
- 发布日期: 2018-10-24

Analytic solution for wave propagations in layered unsaturated soil and its application

1. School of Civil Engineering and Architecture, Beijing Jiao-tong University, Beijing 100044, China;
2. Shanghai Langxin Real Estate Development Co., Ltd., Shanghai 201306, China;
3. MCC Capital Engineering Research Incorporation Limited, Beijing 100176, China

摘要

摘要: 现有地基场地波动问题研究中,多将地基土视为饱和、准饱和状态或单相介质,难以反映非饱和土体波动性质。在现有非饱和多孔介质波动理论的基础上,建立基岩上覆成层非饱和土复杂场地模型,采用传递矩阵法,分别求解了平面P波和SV波入射下基岩上覆成层非饱和土场地波动问题的解析解。通过与已有的基岩上覆单一非饱和土层波动问题的解进行对比,验证了该解的正确性。并利用该解答初步分析了当非饱和土层饱和度呈梯度变化时,地下水水位变化对地面运动的影响。分析结果表明：地下水位变化对地面运动的影响与入射波频率和入射角有关。相同频率下,当入射角较小时,地下水位变化对地表竖向位移的影响较大;地下水位变化对水平位移的影响随着入射角增加先增加后减小。相同入射角下,随着地下水位上升,地表竖向位移的峰值减小,峰值频率增加,而地表水平位移的峰值及峰值频率变化不大。
- 非饱和孔隙介质 /
- 成层场地 /
- 地面运动 /
- 地下水位 /
- 平面波
Abstract: In most of the current analyses of free field seismic response, the unsaturated soils are usually regarded as the quasi-saturated or single-phase media. It is difficult to describe the characteristics of unsaturated soils. A free field model for rock-layered unsaturated soil system is established. Based on the theory of wave motion in poroelastic medium, the elastic wave propagation under plane P-wave and SV-wave incidence in the rock-layered unsaturated soil system is solved using the transfer matrix method. By comparison with the existing solutions for an overlying unsaturated soil layer on the bedrock half-space, the solution given here is verified. Assuming the saturation of the soils above the groundwater layer has a gradient variation along the depth, the effects of variation of groundwater level on earthquake ground motions are analyzed using this solution. It is shown that the effects of variation of groundwater level on ground motions are related with the wave frequency and incident angle. At the same frequency, the variation of groundwater level has a great effect on the vertical displacement at ground surface when the incident angle is small. The effect of the groundwater level on the horizontal displacement first increases and then decreases with the incident angle increasing from 0° to 90°. At the same incident angle, the response peaks of the vertical displacement at ground surface decrease, and the frequencies of the resonance peaks increase with the increase of the groundwater level. But the variation of groundwater level has little effects on the horizontal displacement at ground surface.
- unsaturated porous medium /
- layered unsaturated soil /
- earthquake ground motion /
- underground water /
- plane wave

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参考文献(19)

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