DYNAMIC CHARACTERISTICS OF STRUCTURES WITH MULTIPLE TUNED MASS DAMPERS

Effectiveness of multiple tuned mass dampers (MTMD) in suppressing the dynamic response of base excited structure for first mode vibration i s investigated. The effectiveness of the MTMD is expressed by the rati o of the root mean square (RMS) displacement of the structure with MTM D to corresponding displacement without MTMD. The frequency content of base excitation is modelled as a broad-band stationary random process . The MTMD's with uniformly distributed natural frequencies are consid ered for this purpose. A parametric study is conducted to investigate the fundamental characteristics of the MTMD's and the effect of import ant parameters on the effectiveness of the MTMD's. The parameters incl ude: the fundamental characteristics of the MTMD system such as dampin g, mass ratio, total number of MTMD, tuning frequency ratio, frequency spacing of the dampers and frequency content of the base excitation. It has been shown that MTMD can be more effective and more robust than a single TMD with equal mass and damping ratio.