Control of Full-Size Frame Structures via Optimum Tuned Mass Dampers

Background

Tuned Mass Damper (TMD) is a conventional technical device consisting of a mass, spring, and viscous damper. It is typically attached to a vibrant primary structural system to reduce the dynamic response induced by wind and seismic loads. The frequency of the damper is adjusted to a primary structural frequency so that when this frequency is excited, the damper will resonate out of phase with the structural motion. By pre-setting, the calculated spring stiffness, damping factor, and mass, the system can have a good vibration reduction effect and the energy is dissipated by the inertia force of the damper acting on the structure. Tuned mass damper (TMD) is the main representative of vibration reduction methods in passive damping systems. With alternative advantages like simple structure, useful design, and pronounced vibration damping effects, it is widely used in civil engineering structures to reduce vibrations due to strong wind and earthquake loads.

Structural vibration analysis is essential for the calculation of the natural frequencies of a structure and the response to the expected excitation. The structural response may occur in several ways including the change of the mass or stiffness of the structure, the moving of the source of excitation to a different location, or the increase of the damping provided in the structure. Tuned mass dampers are special cases of vibration dampers. The theory of vibration absorbers and adjusted mass dampers are discussed with real-life applications. One way to reduce structural vibration under dynamic excitations is to install dampening devices in buildings.