Evaluation of elastically linked dashpot based active multiple tuned mass dampers for structures under ground acceleration

The elastically linked dashpot based active multiple tuned mass dampers (ELD-AMTMD) have been developed in this paper to assess the effects of installing elastically the dashpots on the control performance of the active multiple tuned mass dampers (AMTMD) with resorting to the stiffness ratio. The criterion for assessing the optimum parameters and effectiveness of the ELD-AMTMD is defined to be the minimization of the minimum values of the maximum dynamic magnification factors of the structure with the ELD-AMTMD. The criterion used to evaluate the ELD-AMTMD stroke is the maximum dynamic magnification factor of every ELD-ATMD. The parametric studies for the effects of the stiffness ratio on the control performance of the ELD-AMTMD are then carried out using the assessment criteria defined above. The effects of the stiffness ratio have also been investigated on the control performance of the elastically linked dashpot based multiple tuned mass dampers (ELD-MTMD, passive counterpart of the ELD-AMTMD), the special case of the ELD-AMTMD with the normalized acceleration feedback gain factor (NAFGF) equal to zero. The studies have shown that there is an upper limit on the stiffness ratio, designated as the maximum allowable stiffness ratio, beyond which the control performance of the ELD-AMTMD/ELD-MTMD will deteriorate.