非饱和土地基振动响应分析

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振动与冲击 ›› 2019, Vol. 38 ›› Issue (12) : 182-190.

论文

非饱和土地基振动响应分析

李伟华1，王文强2

作者信息 +

Vibration response analysis of an unsaturated soil foundation

LI Weihua1,WANG Wenqiang2

Author information +

文章历史 +

摘要

非饱和介质波动理论的发展，使得非饱和土地基动力响应问题求解成为可能。本文根据现有的非饱和多孔介质动力方程，采用解耦技术，建立非饱和多孔介质动力反应分析的显式有限元分析方法，并编制相关计算程序。通过与已有解析解的对比，验证了方法及程序的正确性和精度。利用该方法，分别分析了刚性基础与柔性基础条件下非饱和土地基振动问题，重点讨论了饱和度对非饱和土地基振动响应的影响，结果表明：刚性基础条件下地基的振动响应大于相同条件下柔性基础地基振动响应；土体饱和度Sr=1时地基各点振动比Sr<1时明显减小；刚性基础条件下，Sr<1时，随着饱和度增加各点竖向位移减小，水平位移增大，而柔性基础条件下，Sr<1时，饱和度对地基各点振动的影响有限。

Abstract

The development of the wave theory of unsaturated porous media makes the dynamic analysis of unsaturated soil foundation possible.In this paper, an explicit finite element method for the existing dynamic formulation of unsaturated porous media was proposed.The decoupling-technique was used in the explicit finite element method.Based on the method, the computational program was written and verified by comparing with the analytical solution after degeneration.The method was applied to analyze the dynamic responses of a strip rigid and flexible foundation in an unsaturated porous medium separately, and the influence of saturation on the dynamic responses of unsaturated soil foundation was discussed.The computational results indicate that, the dynamic response of the rigid foundation is larger than that of flexible foundation under the same conditions.For both kinds of foundations, the dynamic response for Sr=1 is smaller than that for Sr<1.For the rigid foundation, the vertical displacement of each point decreases and the horizontal displacement increases with saturation level when Sr<1.For the flexible foundation, saturation has limited influence on the dynamic response of unsaturated soil foundations.

导出引用

李伟华1，王文强2. 非饱和土地基振动响应分析[J]. 振动与冲击, 2019, 38(12): 182-190

LI Weihua1,WANG Wenqiang2. Vibration response analysis of an unsaturated soil foundation[J]. Journal of Vibration and Shock, 2019, 38(12): 182-190

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