Dynamic Responses of a Poroelastic Half Space Generatedby 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.