Optimum parameters of multiple tuned mass dampers for base-excited damped systems

The optimum parameters of multiple tuned mass dampers (MTMD) for suppressing the dynamic response of a base-excited structure in a specific mode is investigated. The base excitation is modelled as a stationary white noise random process. The stationary response of the structure with MTMD is analyzed for the optimum parameters of the MTMD system. The criterion selected for optimality is the minimization of the root mean square (r.m.s.) displacement of the main structure. The parameters of MTMD that are optimized include the damping ratio, the tuning frequency ratio and the frequency bandwidth of the MTMD system. The optimum parameters of the MTMD system and corresponding effectiveness are obtained for different damping ratios of the main structure and mass ratios of the MTMD system. In addition, the effectiveness of an optimally designed MTMD system is compared with that of an optimum single tuned mass damper. It is shown that the optimally designed MTMD system is more effective for vibration control than the single tuned mass damper. (C) 1997 Academic Press Limited