Effects of excitation characteristics on the equivalent linear system of a building structure with MR dampers

MR감쇠기가 설치된 구조물의 등가선형 시스템에 대한 가진 특성의 영향

  • 박지훈 (단국대학교 리모델링연구소) ;
  • 민경원 (단국대학교 건축공학과) ;
  • 문병욱 (단국대학교 건축공학과) ;
  • 박은천 (단국대학교 건축공학과)
  • Published : 2006.03.17

Abstract

Seismic control performance of MR dampers, which have severe nonlinearity, differs with respect to the dynamic characteristics of an earthquake such as magnitude, frequency and duration. In this study, the effects of excitation characteristics on the equivalent linear system of a building structure with an MR damper are investigated through numerical analysis for artificial ground motions generated from different response spectrums. The equivalent damping ratio of the structure with an MR damper is calculated using Newmark and Hall's equations for ground motion amplification factors. It is found that the equivalent damping ratio of the structure with the MR damper is dependent on the ratio of the maximum friction force of the MR damper over excitation magnitude. Frequency contents of the earthquake ground motion affects the equivalent damping ratio of long-period structures considerably. Also, additional damping effect caused by interaction between the viscousity and friction of the MR damper is observed.

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