Robust Design Strategy for Multiple Tuned Mass Dampers with Consideration of Frequency Bandwidth

The tuned mass damper (TMD) has been widely used in vibration control of civil engineering structures after numerous analytical studies and experimental verifications. A large number of TMDs have been implemented in real structures against natural and man-made excitations since the early 1970. From field observations, it was found that the control efficacy of a TMD may decay significantly when its frequency is not well tuned to the desired value. A multiple TMD (MTMD) system was proposed to tune a band of frequencies, thereby enhancing the vibration control efficiency. Frequency detuning usually results from structural system variations due to errors in modeling, construction, and system parameter identification. In this study, the frequency detuning effect due to uncertainties of the controlled system parameters on the performance of the MTMDs is investigated. A sensitivity analysis was first carried out to evaluate the control effectiveness of a MTMD system designed by a conventional method. A new robust design method with account taken of frequency bandwidth is proposed to alleviate the detuning effect. Numerical analysis is performed to verify the applicability and efficacy of the proposed robust design method.