The purpose of this paper is to evaluate the performance of a MR fluid damper for seismic vibration control of a structure in terms of equivalent linear damping or stiffness based on linearization technique and to experimentally verify the results from linearization technique by comparing them to those from system identification of a building structure with MR damper. First, among the various models for MR damper, the equivalent stiffness and damping are estimated for Bingham model which is mathematically simple and for Bouc-Wen model which can describe any kind of hysteretic behavior. Second, transfer function of a building structure with MR damper is obtained by performing shaking table tests and the stiffness and damping matrices of the structure are constructed using the modal information obtained by the transfer function. It is observed that the damping mathematically estimated using linearization technique for Bingham model matches well with the damping coefficient experimentally obtained by system identification.

Piloti structure is a building designed to open the ground floor as a basic principle of modern architecture. However, it is considered urgent to prepare seismic retrofit plans for the irregular torsion problem of the Piloti building through the recent Pohang earthquake. Therefore, this study aims to provide the basic data for the selection of the Piloti building seismic retrofitting method by comparing the dynamic characteristics of each method through the small shaking table experiment using the seismic retrofitting method of the pilotty building.