Optimization criteria for tuned mass dampers for structural vibration control under stochastic excitation

Abstract

In this work a comparative analysis between different optimization criteria is performed for a linear Tuned Mass Damper (TMD) devices problem. Optimal TMD mechanical parameters are evaluated considering a simple one degree-of-freedom system subject to a base acceleration modeled as a stationary filtered stochastic process. Whereas common TMD optimization methods consider only TMD frequency and damping ratio as design variables, in this study a complete approach will be proposed, which takes into account also the TMD mass as design variable. The effectiveness of the vibration control strategy is evaluated expressing the objective function in terms of two different reduction factors of the system response: the displacement and the inertial acceleration, respectively. The mechanical characteristics of the TMD, frequency ratio, damping ration and mass ratio, represent the design variables of the optimization problem. This is carried out numerically and then various analyses of sensitivity are developed by varying the input and structural parameters in order to assess the efficiency of the TMD strategy under different input and mechanical configurations. Variations between different criteria are also evaluated.