基于连续介质力学模型的部分埋入单桩的纵向振动研究

采用连续介质力学模型,考虑桩-土之间的连续条件和边界条件,得到了土体的纵向振动位移,建立了埋入和外露部分桩基的纵向振动微分方程.考虑埋入和外露部分桩基的连续条件和边界条件,求解了部分埋入单桩的纵向振动,并以数值算例的形式讨论了桩基埋入深度和桩土模量比对桩顶复刚度的影响.通过参数分析和讨论,表明部分埋入桩纵向简谐振动存在共振现象,桩基的埋入深度和桩土模量比对桩顶复刚度有较大影响,且桩基外露部分越长,桩顶复刚度随频率变化曲线波动越厉害.

Vertical Vibrations of Partially Embedded Single Pile Based on Continuous Mechanics Model

Considering the continuity conditions and boundary conditions of the pile and soil,the vertical dynamic displacement of the soil was obtained based on continuous mechanics model,and established the vertical dynamic differential equations of the embedded part and exposed part of the pile. The vertical vibration of partially embedded single pile was solved by considering the continuity conditions and boundary conditions of the embedded part and exposed part of the pile,and the influence of the length of embedment of pile and the pile-soil modulus ratio on complex stiffness at pile head was investigated with numerical example. Through the discussion of parameters,it was concluded that the resonance of partially embedded single pile will occur under harmonic dynamic load,and the length of embedment of pile and the pile-soil modulus ratio have great effect on the complex stiffness of the pile at pile head,the fluctuation of the curves of complex stiffness of the pile at pile head varying with frequency will more seriously when the length of exposed part of the pile is longer.