横观各向同性饱和地基竖向振动的衰减特性

基于提出的横观各向同性饱和多孔介质Biot波动方程的一般解，研究了饱和半空间地基在竖向点源简谐激振荷载作用下地表振动的衰减特征，分析了激振频率以及横观各向同性饱和土介质的各向异性参数和孔隙渗透系数对地表振动特征的影响。计算结果表明，低频和高频激振时，地表位移衰减特性存在明显差异；在饱和土的各向异性参数中，纵向和水平方向动态渗透系数比值和刚度系数比值对地表位移衰减影响最大，这也说明采用各向同性饱和介质的动力学模型不能准确地描述具有明显各向异性特性的饱和土地基的动力特性。

Vibration attenuation of transversely isotropic saturated strata under vertical surface loads

Based on the general solutions of Biot’s wave motions of transversely isotropic saturated poroelastic media established by the author，the vibration attenuation at ground surface under the point harmonic excitation is researched. And the combined effects of the soil permeability and the loading frequency on the results are analyzed. The calculation results indicate that the characteristics of vibration attenuation of vertical displacement under the low and the high exciting frequencies are different obviously. Of all the parameters of transversely isotropic saturated media, the rates both in osmotic coefficient and in elastic constants between vertical and horizontal direction influence the vertical vibration attenuation mostly. The results also indicate that adopting dynamic model of isotropic saturated medium could not describe exactly the dynamic characters of the saturated poroelastic medium that has obviously anisotropic properties.