高速荷载下多孔饱和地基的动力响应

研究高速荷载作用下梁与多孔饱和半空间的动力响应。由Fourier变换求解多孔饱和固体的动力基本方程，根据梁与半空间的接触条件得出多孔饱和半空间上梁的垂直位移的表达式。文中的数值算例考虑了荷载移动速度对梁的动力位移的影响，并与相应的弹性半空间问题作了对比。从算例中可以发现荷载移动速度对动力位移有很大的影响，当移动速度与半空间的表面波速相近时，地面会当产生很大的振动，同时还发现当速度大于介质的剪切波速时，多孔饱和半空间上梁的动力响应与弹性半空间上梁的动力响应有很大的差别。

Dynamic Responses of a Poroelastic Half Space Generated by High Speed Load

The dynamic response of a beam on a poroelastic half space generated by high speed load was studied. The dynamic fundamental equations for poroelastic solid were solved by use of Fourier transform. The expression of the vertical displacement of the beam was obtained according to the contact condition between a beam and a half space. In the numerical study, the effects of the load velocity on the dynamic displacement of the beam were considered and the comparison of solutions corresponding to two different materials (elastic material and poroelastic material) was presented. It is found that the load velocity has significant influence on the dynamic displacement. When the moving velocity is close to the Rayleigh wave speed, the displacement on the surface of the half space will become very large. It is also noted that the large differences exist between the dynamic responses for a beam on a poroelastic half space and an elastic haff space when the load velocity is larger than the shear wave speed of the medium.