Abstract: In order to study the seismic response of the interaction systems assembled by multi-ribbed composite wall structure and subsoil in frequency domain, a series of shake table tests was carried out using a model scaled in 1/15. The dynamic responses of the structure and subsoil were studied by inputting white noise, El-Centro wave, Tianjin wave in the tests. The response curve was obtained in frequency domain by Fast Fourier Transform, and the dynamic characteristics of the foundation and structure as well as their dynamic responses from 7 degree to 9 degree along horizontal axis loading were analyzed. The frequency response curves of the acceleration and displacement under different loading conditions were comparatively investigated. The dynamic frequency responses of the foundation and structure and their influencing factors were also examined. It was found that the fixing effects of subsoil for the superstructure are lessened, and the vibration frequencies decrease after the subsoil crack affected by the earthquake wave. The acceleration responses are amplified at the subsoil surface and the structure top with increasing the intensity, the frequencies corresponding peak response vary remarkably. The amplification effect of foundation on acceleration is remarkable, and the amplification effect of superstructure on displacement is significant. Therefore, the dynamic amplification effect is closely related to the destruction of subsoil and earthquake ground motion characteristics when considering the interaction between subsoil and structure.

Key words: multi-ribbed wall structure, interactions, dynamic response in frequency domain, shake-table test