Input and System Identification of the Hualien Soil-structure Interaction System Using Earthquake Response Data

Abstract

This paper presents an input and system identification technique for a soil-structure interaction system using earthquake response data. Identification is carried out on the Hualien large-scale seismic test structure, which was built in Taiwan for international joint research. The identified quantities are the input ground acceleration as well as the shear wave velocities of the near-field soil regions and Young's moduli of the shell sections of the structure. The earthquake response analysis on the soil-structure interaction system is carried out using the finite element method incorporating the infinite element formulation for the unbounded layered soil medium and the substructured wave input technique. The criterion function for the parameter estimation is constructed using the frequency response amplitude ratios of the earthquake responses measured at several points of the structure, so that the information on the input motion may be excluded. The constrained steepest descent method is employed to obtain the revised parameters. The simulated earthquake responses using the identified parameters and input ground motion show excellent agreement with the measured responses.