In this research, our team developed a semi-active MR damper by designing and producing it, and also evaluated its performance for the control of large structure. It is specially designed to have a flexible capacity to control a range of 10KN-30KN with an input current of 0 - 3A. The evaluation of its performance was carried out; first, to input a 0 - 3A electric current at various frequence range between 0.15Hz and 2Hz, then to measure a consequent power and displacement. By finding that the MR damper secures a control capacity of 10KN-30KN, it was proved that the MR damper is capable to control any large structure.

In this research an experimental study was carried out to decrease the damage caused by the collision of bridges as earthquake load was added. For the experiment, we designed a model of successive bridge composed of a reinforced concrete bridge top and I section steel. As for damper, we ourselves designed and produced a MR damper of 30 KN. The result proved that the MR damper of our own design was effective to prevent the successive bridge model from colliding.

본 논문에서는 무선 센서 네트워크를 이용한 피드백 진동제어 시스템을 구성하고, 모형 구조물을 대상으로 구성된 시스템의 진동제어효과를 실험적으로 검증하고자 하였다. 이를 위하여 본 논문에서는 블루투스 기반의 무선 I/O 센서 시스템과 스마트 재료를 사용한 전단형 MR 댐퍼를 개발하고, 또한 일정한 크기의 정현파형을 발생시키는 가진기 및 모형 단순보 구조물을 이용하여 피드백 진동제어 시스템의 실험?V을 구성하였다. 진동제어 실험은 가진기를 이용해 보의 1/4 등분점에서 일정하게 가진한 상태에서, 보 중앙점에 수직방향으로 설치된 MR 댐퍼를 이용해 진동을 제어하였으며, 보의 2/4 등분점에서의 가속도 응답을 획득하여 제어효과를 평가하였다. 이때, 제어명령은 보 중앙점에 무선 I/O 센서 노드를 설치하고, 여기서 획득된 가속도 응답이 일정 크기 이상일 경우에 설정된 범위의 전압신호를 MR 댐퍼로 출력하도록 설정하였다. 최종적으로 본 논문에서 구성된 무선 센서 네트워크 기반의 실시간 피드백 진동제어 시스템은 비록 제한적인 명령 체계에서 검증되었지만, 실시간적으로 목적된 제어명령의 발생시킴으로써 구조물의 진동을 효과적으로 감소시키는 것을 확인하였고, 추후 다양한 준능동 제어 알고리즘을 적용한 구조적 응답제어시스템으로의 활용 가능성을 제시하였다.

In this paper, an experimental research was carried out to compare the capability to control a MR-damper attached structure, which turned out to differ according to its vibration control direction whether vertical or horizontal. The target structure for the experimental test was a real size asymmetrical cable-stayed bridge. The MR-damper for vibration control was designed 30KN to fit into the target bridge. For the performance experiment of the MR-damper, the el-centro earthquake wave using three shaking table was inflicted on the model bridge structure, once horizontally and then vertically. Finally, each control capability, different according to its direction, was compared and evaluated. The experiment proved that the MR-damper was able to damp in a different way according to its control direction(horizontal or vertical) and also to work effectively damping the acceleration responses of the structure.