Magneto-Rheological Fluid (MRF) is a functional fluid in which flow characteristics change into magnetic force due to its magnetic particles. When the semi-active control device does not use MRF for a long time, precipitation of magnetic particles and abnormal control force occur. Thus, Electro Magneto-Rheological Fluid (EMRF), which improves the precipitation of magnetic particles for MRF and exhibits existing control performance, was developed in this study. First, the optimal mix proportion ratio was selected by conducting a precipitation experiment and a controlled force test by varying the content of grease based on the existing MRF components. Also, EMRF was applied to the shear-type damper to evaluate the control performance when applied to the control device. The cylinder-type damper was developed to apply to the structure, and control performance evaluation was conducted. The result confirmed that the precipitation of the magnetic particles was improved, while the damper using EMRF exhibited excellent control performance.

ABSTRACT
1. 서 론
2. 자기유변유체
    2.1 MRF(Magneto Rheological Fluid)
    2.2 EMRF(Enhanced Magneto Rheological Fluid)
3. EMRF 개발
    3.1 샘플 제작
    3.2 시간에 따른 침전율 비교
4. EMRF Damper 개발
    4.1 EMRF Damper 설계
    4.2 EMRF Damper의 제어 성능평가
    4.3 동적 모델링 비교
5. 결 론
REFERENCES

• 전승곤(충남도립대학교 건설안전방재학과 초빙교수) | Jeon, Seung gon (Visiting Professor, Dept. of Construction Safety & Disaster Prevention, Chungnam State University) Correspondence author