Massdämpningssystem

Massdämpningssystem, also known as tuned mass damper (TMD), is a passive control device used to reduce wind-induced vibrations and other dynamic forces in structures. It consists of a mass, a spring, and a damping mechanism, typically a viscous damper. The system is tuned to resonate at the same frequency as the structure's dominant mode of vibration. When the structure is excited by external forces such as wind or earthquakes, it begins to oscillate. The TMD, being attached to the structure, also starts to oscillate. The kinetic energy of the oscillating mass is absorbed by the damping mechanism, which dissipates the energy as heat. This action counteracts the structural vibrations, reducing their amplitude.

The effectiveness of a TMD depends on its mass, stiffness, and damping coefficient, as well as its placement on the structure. Larger TMDs are generally more effective but also heavier and more costly. Optimal placement is usually at or near the point of maximum displacement of the vibrating mode. TMDs are widely used in tall buildings, bridges, and other structures where vibration control is critical for comfort, safety, and structural integrity. They are particularly effective against harmonic or resonant vibrations. While TMDs are a passive system and require no external power source, their design and tuning can be complex, often requiring sophisticated dynamic analysis. Other types of vibration control systems exist, such as active mass dampers (AMDs) which use actuators to actively counteract vibrations, and semi-active damping systems.