下卧基岩层状各向异性地基上刚性圆形基础竖向振动特性分析

Based on elastodynamic theory, the vertical vibration characteristics of a rigid circular foundation resting on a layered anisotropic subgrade underlain by bedrock are investigated using a semi-analytical method. By introducing a novel Fourier-Bessel series vector function system combined with the dual-variable and position method, the Green ' s function corresponding to a vertical circular load applied on the surface of a layered anisotropic elastic subgrade is derived. Using the superposition method, the influence function under a vertical annular load is obtained. The integral least-squares method is employed to determine the densities of the discretized annular loads within the foundation-subgrade contact region, and the vertical dynamic compliance coefficient of the rigid foundation is then obtained from the vertical force equilibrium condition. Through parameter analysis, the effects of the anisotropic modulus ratio, thickness, layering, and heterogeneity of the subgrade soil on the dynamic interaction between foundation and subgrade soil are systematically investigated. The results indicate that the introduction of discretized Love numbers significantly improves the overall computational efficiency, while soil anisotropy markedly affects both the vertical dynamic compliance coefficient of the foundation and the vertical displacement distribution of the subgrade.