DAMPING CHARACTERISTICS OF AN ENTIRE HIGHWAY BRIDGE SYSTEM ESTIMATED BY SYSTEM IDENTIFICATION BASED ON THE SUBSPACE METHOD

Abstract

 The damping characteristic is an important parameter in the design calculation of the structure. In this study, the natural period and damping characteristics of the entire bridge system were calculated from the continuous behavior observation records of the entire bridge system using the observation records of weak earthquakes and the records of constant vibration. System identification based on the subspace method was used to calculate the natural period and damping characteristics. The purpose of this study was to develop a method for calculating the vibration characteristics of the entire bridge system, and verified the applicability of the subspace method for multipoint observation records of bridges. As a result, the average value of the mode attenuation of the entire bridge system of the target bridge in this study was evaluated as h = about 1.7% by system identification based on the subspace method.