Vertical Vibrations of Elastic Foundation Resting on Saturated Half-Space
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摘要: 采用解析的方法研究了饱和地基上受一简谐竖向荷载作用下弹性基础的动力响应.在分析中,首先利用积分变换技术获得了饱和介质基本控制方程的变换解,然后基于基础-半空间完全放松接触、半空间表面完全透水或不透水的假设,建立了该动力混合边值问题的对偶积分方程,并把该对偶积分方程进一步化为易于数值求解的第二类Fredholm积分方程A·D2文末数值算例给出了动力柔度系数、位移和孔隙水压力随振动频域和土-基础体系物理力学参数特性的变化曲线.结果表明:饱和地基上弹性基础的动力响应完全不同于饱和地基上刚性圆板的动力响应.所用方法可用于研究波的传播、土-结构动力相互作用等许多问题.Abstract: The dynamic response of an elastic foundation of finite height bonded to the surface of a saturated halfspace is mainly concerned with. The foundation is subjected to time-harmonic vertical loadings. First, the transform solutions for the governing equations of the saturated media were obtained. Then, based on the assumption that the contact between the foundation and the halfspace was fully relaxed and the half-space was completely pervious or impervious, this dynamic mixed boundary-value problem can lead to dual integral equations, which can be further reduced to the Fredholm integral equations of the second kind and solved by numerical procedures. In the numerical examples, the dynamic compliances, displacements and pore pressure are developed for a wide range of frequencies and material/geometrical properties of the saturated soilfoundation system. In most cases, the dynamic behavior of an elastic foundation resting on the saturated media significantly differs from that of a rigid disc on the saturated half-space. The solutions obtained can be used to study a variety of wave propagation problems and dynamic soil-structure interactions.
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Key words:
- saturated medium /
- elastic foundation /
- vertical vibration /
- dynamic compliance /
- dual integral equation
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