Robust Passive and Active Dampers

During their lifetimes, flexible structures may experience natural frequency changes under wind speed, ambient temperatures and relative humidity variations, among other factors, which make the tuned mass damper (TMD) design challenging. In this study, a proposed approach for the design of robust TMDs is presented and investigated. The approach accounts for structural uncertainties, optimization objectives and input excitation (wind or earthquake). For the use of TMDs in buildings, practical design parameters can be different from the optimum ones. However, predetermined optimal parameters for a primary structure with uncertainties are useful to attain design robustness. The proposed approach showed its robustness and effectiveness in reducing the response of tall buildings under multidirectional wind loads. In addition, LQG and fuzzy logic controllers may enhance the performance of the TMD.

Placement of viscous dampers with a lever mechanism shows that higher reductions in responses can be achieved with smaller damping devices. Stiffness uncertainty and damper failure are considered to check the robustness of the mitigation system. The study shows that viscous dampers are a viable solution for vibration attenuation in high-rise buildings susceptible to wind and earthquake loads, which permits the minimization of structural and nonstructural damage by counteracting multi-hazard forces in real-time. Viscous dampers show their potential to enhanced dynamic performance of buildings under multiple hazards and can directly promote community resiliency.

Robust Passive and Active Tuned Mass Dampers

Outer Bracing System

Selected Publications