桩顶固定且部分桩体埋入黏弹性地基中时桩的自振特性分析

将回传射线矩阵法推广至桩土系统的振动分析中,采用基于Timoshenko梁理论的Winkler地基模型,运用回传射线矩阵法及求根法求解桩顶固定且部分桩体埋入弹性地基中时桩的自振特性,并与基于有限元分析软件SAP2000的计算结果比较,验证利用回传射线矩阵法求解埋置结构自振特性的有效性和计算精度。同时,分析桩顶固定且部分桩体埋入黏弹性地基中时土体弹簧系数及土体阻尼系数对桩基自振频率和振型的影响。结果表明:随着土体弹簧系数的增大,埋置结构的各阶自振频率增大,土体弹簧系数对衰减系数没有影响,对埋置结构振型的影响较小;随着土体阻尼系数的减小,埋置结构的各阶自振频率增大,衰减系数相应减小,土体阻尼系数对埋置结构的低阶振型影响尤为明显,对高阶振型的影响较小。

Analysis of Vibration Characteristics of Piles with Top Fixed and Part Embedded in a Viscoelastic Foundation

Extending the reverberation-ray matrix method analysis to the vibration of pile foundation, Based on the Winkler foundation model of Timoshenko beam theory,the vibration characteristics of pile with top fixed and part embedded in elastic foundation were solved by the reverberation-ray matrix method and the root method,the calculation result were compared with SAP2000,it shows that the effectiveness and accuracy of the vibration characteristics of the buried structure were solved by the reverberation-ray matrix method.Meanwhile,the influence of soil spring coefficient and soil damping coefficient on the natural frequency and mode of pile with top fixed and part embedded in viscoelastic foundation was analyzed, the results show that when the soil spring coefficient increases, the natural frequency of the embedded structures increases, the soil spring coefficient has no effect on attenuation coefficient,and the influence of embedded structure mode is small. when the soil damping coefficient decreases, the natural frequency of the embedded structures increases, the attenuation coefficient of the embedded structures decreases, and the influence of the embedded structures on the low-order modes is especially obvious, and the influence on the high-order modes is small.