Nonlinear Controllers for Active Composite Tuned Mass Dampers

Abstract

This paper considers nonlinear control of buildings utilizing composite tuned mass dampers subject to earthquake. Basically composite tuned mass dampers are tuned mass dampers having two dampers connected in series, where auxiliary mass dampers as satellite damper is attached on the first dampers. The properties of composite tuned mass dampers are optimized before they are used in the structures. Active control systems are then applied to the composite tuned mass dampers. Because the magnitude of control force is not unlimited, the maximum energy to be supplied to the building should be bounded within the actuator's capacity. Several combinations of active control locations are investigated, i.e., two controllers at both dampers, one controller at first damper only, and one controller at the second damper only. Continuous bounded control algorithms utilizing continuous function are used as the control algorithms in this paper. From the numerical simulations, it is found that the best result is obtained when both control forces are applied to the mass dampers. In the case that only one actuator is used, better performance is achieved when the control force is applied at the first (bottom) damper.