Hey

Tuned ( talking about the frequency of the TMD) it means adjusting the frequency of this system (secondary system) to a specific frequency of the primary system generally the dominant frequency (the First one).

Hi Mekdes,

Mass dampers are characterised by a frequency (or frequency band) in which they operate. This frequency depends on the mechanical characteristics of the damper (mass and spring and less on damper) or on electronic characteristics, in case there is a motor or an electronic system involved. So the term 'tuned' lies on the fact that the engineer can actually change the aforementioned frequency band by atlering ('tuning') the mechanical and/or electronic characteristics of the mass damper.

Hope I 've helped somehow.

All the best,

Theofanis.

The main idea of the system, i.e. structure with TMD, is to match the frequency of the TMD to the inherent frequency of the structure itself. That is to say, if the structure’s frequency is 0.2 Hz for example, the TMD should be designed to a frequency that is exactly the same or close to this value, hence “TUNED”. If this is achieved, then the TMD will be effective and the vibration of the structure will be controlled, likewise, acceleration will subside more efficiently. If not, then the structure may either be inadequate in serviceability when the TMD’s frequency is higher or may cause detrimental effects when the TMD’s frequency is lower than that of the structure itself