Hybrid Time/Frequency Domain Identification of Real Base-Isolated Structure
Paper i proceeding, 2016

This paper presents a case study using hybrid time-and frequency-domain identifications in a synergistic manner to develop models of a full-scale experimental base-isolated structure. This four-story reinforced-concrete building on an isolation layer (of rubber bearings, elastic sliding bearings, passive metallic yielding dampers, and controllable oil dampers) was designed and constructed at the large-scale Japanese NIED E-Defense earthquake engineering laboratory. A variety of sensors, including accelerometers, were mounted within the structure to measure building response to shake table excitations. While the building was ultimately subjected to historical and synthetic ground motions, the recorded table and building accelerations during a number of random excitation tests are used to identify the structure's natural frequencies, damping ratios and mode shapes. The substantial damping provided by the isolation layer necessitates adopting a hybrid time-and frequency-domain approach for identification. The modes of the structure are separated by frequency content wherein lower frequency modes are identified using time domain approaches from the subspace identification family of methods and higher frequency modes are identified using frequency response functions. Individually, neither approach is able to successfully identify all of the desired modes but, through their combination, the modal properties of the structure are successfully characterized.

State-space models

Base-isolation

Full-scale testing

Frequency response functions

Modal analysis

Författare

P. Brewick

University of Southern California

W. M. Elhaddad

University of Southern California

Erik A. Johnson

University of Southern California

Thomas Abrahamsson

Dynamik

E. Sato

National Research Institute for Earth Science and Disaster Prevention (NIED)

T. Sasaki

National Research Institute for Earth Science and Disaster Prevention (NIED)

Dynamics of Civil Structures : Proceedings of the 34th IMAC, A Conference and Exposition on Structural Dynamics 2016

2191-5652 (eISSN)

Vol. 2 303-311

Ämneskategorier

Maskinteknik

DOI

10.1007/978-3-319-29751-4_31

ISBN

978-3-319-29751-4