The Computation For Dynamic Response With Drainage Of In The Saturated Soil Under Buried Loading By The Green’s Function Of Relaxation In Radial Direction And It’s Engineering Application

There frequently happening are the sand blasting and water drainage in a saturated sandy soil, when an earthquake takes place. Similar phenomena happen during pile driving also, It can also cause a lot of drainage when doing foundation treatment with vibroflotation method. However, the computation on drainage can’t be carried out so far. By mathematical deduction in theory, while the aid of numerical solution of the boundary element method, This paper calculated the dynamic response of saturated soil. The application of Green function can reduce the dimension of the problem and the amount of calculation. Boundary element method can combine numerical methods with analytical solutions, and facilitate handling infinite domains and semi-infinite domain problem. Therefore, It has been used widely in the field of geotechnical engineering, underground engineering and hydro-structure.Based on the previous research, and on the basis of decoupling theory that Professor Ding Boyang have solved, this paper conveniently obtained the Green’s functions of the solid and fluid phases in frequency domain in a saturated half-space foundation subjected to a buried point loading, and discussed the dynamic properties of saturated soil, such as the displacement, pore pressure.Secondly, using reciprocal theorem, this paper derived somigliana equation under the Laplace domain, employing decoupling theory, this paper deduced Lamb’s integral with drainage. Then this paper discussed the dynamic properties of saturated soil under different embedment depth in frequency domain and time domain, such as the displacement, pore pressure and the flux.Finally, The basis of the previous chapters, the paper obtained dynamic properties of saturated soil under the harmonic and intermittent load, That simulates working process of vertical vibroflot. The authors hope to further improve the calculation of vibroflotation drainage problems.then the paper obtained The relative displacement response spectra of earthquake with drainage through Lamb integral equation in time domain, Green function of the two-phase saturated medium and Qian An earthquake strong motion records. According to Simplified expressions of the seismic response spectrum, the paper obtained earthquake relative velocity response spectrum and absolute acceleration response spectrum.contrasting with the response spectrum with undrainage, the paper analysed the impact of drainage on the earthquake response spectrum.