Optimum design of pendulum-type tuned mass dampers

The equations of motion are derived for a translational single degree of freedom system equipped with a 'pendulum-type' tuned mass damper (TMD) under dynamic force and base acceleration excitations. The complex frequency response functions are obtained. Following response minimization procedures, the optimum parameters of the TMD under random white noise excitations are determined. The effect of the TMD in reducing the response is expressed in terms of an equivalent viscous damping. The optimum design parameters and the corresponding efficiency of the TMD under both wind and earthquake dynamic loads are presented in design charts. The effect of the structure inherent and aerodynamic damping on the optimum parameters is studied and simplified charts to account for such effect are provided. Moreover, a design chart for the over-optimum-damped TMDs is presented. The translational-type TMD is treated as a special case of the pendulum-type. Copyright (c) 2005 John Wiley & Sons, Ltd.