In this paper

a specific project site which has deep overburden and soft soil layers is considered. According to the in situ results of soil layer dynamic parameters and dynamic tri-axial test

the seismic effects and seismic response characteristics of the site are discussed based on earthquake response analysis of soil layers. Comparing the caculated acceleration spectra of different earthquake levels （with exceedance probabilities of 63%

10% and 3% respectively in 50 years） with the Aseismic Design Code （JTT004-89）

the limitation of existing design spectrum of the existing code is analyzed. It is not safe to use the code spectrum for project aseismic design of the site. The results are of practical use

and can be used for reference in other similar projects.