Tuned mass damper

Hoang N., Fujino Y., Wamitchai P., 2008. Optimal tuned mass damper for seismic ap>plication and practical design formulas. Engineering Structures 30,707-715. 

Without a tuned mass damper, the top floors of very tall buildings can sway back-and-forth 30 centimeters or more in a strong wind, let alone an earthquake. 

He proposed an example that uses this flow chart to design a 70 m footbridge. He found that dynamics was the dimensioning criterion. If one wants a first natural frequency larger than 5 Hz, one needs to reduce the stress level to an unacceptable level. Therefore one can use a Tuned Mass Damper to attenuate the accelerations in... 

A very important gain in volume can be achieved if one uses tuned mass dampers. An example, with parametric analysis, shows clearly that one needs to consider a design for stiffness approach when dynamic loads are important. 

A multi-objective robust criterion for tuned mass dampers optimal design... 

ABSTRACT This work proposes a robust optimization criterion of mechanical parameters in the design of linear Tuned Mass Dampers (TMD) located at the top of a main structural system subject to random base accelerations. The dynamic input is modelled as a stationary filtered white noise random process. The aim is to properly consider non-uniform spectral contents that happen in many real physical vibration phenomena. The main structural system is described as a single linear degree of freedom, and it is assumed that uncertainty affects the system model. The problem parameters treated are described as random uncorrelated variables known only by the estimation of their means and variances. Robustness is formulated as a multi-objective optimization problem in which both the mean and variance of a conventional objective function (OF) are minimized simultaneously. Optimal Pareto fronts are obtained and results show a significant improvement in performance stability compared to a standard conventional solution. 

A Tuned Mass Damper (TMD) is one of the simplest and the most rehable passive device for vibration control in a wide range of applications, and for this reason many optimization criteria have been proposed for this specific device. Essentially, a TMD consists in an additional mass connected to a main system by a spring and a damper. The main system, excited by a base acceleration, is modelled as a stochastic stationary coloured noise and introducing the global space state vector ... 

Marano, G.C., Greco, R., Trentadue, F. Chiaia, B. 2007. Constrained reliability-based optimization of linear tuned mass dampers for seismic control . International Journal of Solids and Structures, accepted for publication. 

The time delay between the beginning of a dynamic response and the counteraction of TMD is one of the most important topics in structural control (passive and active) from an engineering point of view. Therefore, Koshika et al. [193] have proposed an active-passive composite tuned mass damper (APTMD). The feasibility and the practicability of the theory was confirmed by demonstrating its control effect using an experimental model, as Fig. 8.50 shows. 

The most recent implementations are combinations of add-on devices. While mass dampers provide the majority of implementation (i. e., tuned mass dampers, active mass dampers, hybrid mass dampers), active stiffening or bracing systems, energy dissipation/absorption dampers and hybrid isolations were also implemented in actual applications or full scale experiments. It was noted in [188] that most of the systems were considered as add-ons and the integration of the systems into structural design is not yet completely developed. That is important in relation to the application of active control from practical (engineering) aspects. 

Koshika, N. et al. Research, development and application of active-passive composite tuned mass dampers. Proc. 4th Int. Conf. on Adaptive Structures, Technomic (1993)... 

Wang, J. K, Lin, C. C. (2005). Seismic performance of multiple tuned mass dampers for soil-irregular building interaction systems. Inter-nationalJournal of Solids and Structures, 42(20), 5536-5554. doi 10.1016/j.ijsolstr.2005.02.042... 

Optimal Design and Practical Considerations of Tuned Mass Dampers for Structural Control... 

OPTIMAL DESIGN OF MULTIPLE TUNED MASS DAMPERS... 

Figure 2. A multistory building equipped with multiple tuned mass dampers (Lin et al, 2010)...

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