The Analysis Of Impedance Matrix Of Foundations On Fluid-filled Poro-elastic Medium

It is important to calculate the impedance matrix of foundations in dynamic foundation design and the substructure analysis of the soil-structure interaction.The impedance matrix of foundations on fluid-filled poro-elastic medium, complicated and difficult to resolve using analytical methods, is much concerned in engineering in last decades. In this thesis, a time domain solution method of impedance matrix of foundations on fluid-filled poro-elastic medium was provided. The work was as follows:(1) Based on theory of wave propagation and the method of lumped-mass explicit finite element and local transmitting artificial boundary, an efficient time domain method of impedance matrix of foundations on fluid-filled poro-elastic medium is introduced and the corresponding program was programmed.(2) The numerical analysis of impedance functions of surface and embedded foundations on homogeneous fluid-filled poro-elastic medium half-space was given. Parameters (Poisson ratio, void ratio and permeability coefficient) which effect impedance functions were discussed by the examples.(3) When the values of void ratio and the modulus in compression of fluid phase are zero, the impedance matrix of foundation on fluid-filled poro-elastic soil will be reduced to that of foundation on elastic soil. In this way, the impedance matrix of foundations on the layered stratum which consists of the fluid-filled poro-elastic medium and the elastic medium can be resolved. The numerical analysis of impedance functions of surface and embedded foundations on elastic soil placed on the fluid-filled poro-elastic half-space were done and the effect of elastic soil thickness and the embedded depth on impedance were investigated.(4) Finally, works in this paper were summarized and suggestions on further research were given.