• Journal of the Earthquake Engineering Society of Korea
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• v.2 no.4
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• pp.103-114
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• 1998

The floors of building structures equipped with vibrating machines can be susceptible to large vibration as a result of resonance or beating. Such a vibration can be reduced efficiently by using tuned mass dampers. However, the effectiveness of the damper depends greatly on the location and the natural frequency of the damper. To determine the optimum damper location is especially important since the dynamic behavior of a building structure varies with the location of the input loading. To this end, it is intended to decide the location and natural frequency of tuned mass dampers for reducing vibration of both loaded floors and floors located nearby the loaded floors considering the location and frequency components of the loading. The Vector composition method and the super elements are used th obtain the responses in steady states, and the optimum damper location and natural frequencies were found with the given damper mass.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.26 no.6
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• pp.463-470
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• 2013

In this paper, 2D simple analyses were performed in order to predict the large torsional oscillations in a suspension bridge based on Makenna and Tuama model(2001). The existing model(Makenna and Tuama, 2001) has shown unrealistic results as the wind speed increases and frequency decreases. Furthermore, resonance could not be simulated by the existing model. Therefore, in this study, new model was proposed with a consideration of the torsional resistance. The vertical and rotational behaviors of the deck in the suspension bridge were analyzed. Analysis results showed that at first vertical oscillations were observed and it was gradually transformed to the rotation oscillations. With the consideration of the torsional resistance, it was shown that vertical behavior were stabilized as time passed. However, the rotational behavior was not stabilized and was kept until the end of analysis. Beat periods decreased while the wind speed increased. The resonance of the rotational mode was dependent to the rotational resistance. Obtained results could be applied for the design of the suspension bridge under the wind load.