TMD (tuned mass damper)

Hello,
I wonder how I can model a TMD (tuned mass damper) on my bridge?
The TMD as you know is composed of a mass, springs and dampers.

Should I model it simply by a spring and a concentrated mass? or there is a special function or some other rules to respect !?
In this situation how can we determinate eigenvalues considering the damping of the structure + that of TMD ?

Can you send me please any example of TMD study?

Thanks,

Hello

Yes, a tuned mass damper can be modeled by a spring (SOFiMSHA SPRI) and a mass (SOFiMSHA MASS). The damping of the spring can be defined in lateral (DT) or axial direction (DP).

The eigenvalues can be calculated with the command “EIGE” in DYNA.

Here a short example for a passive TMD:
https://sofistik-my.sharepoint.com/:u:/g/personal/jfh_nbg_sofistik_de/EVTv0v-PZadJl56SgUPMGbIBR6lFKSjJ2c4dLPc-qtqCjg?e=wq4BRA

Best regards
Frederik Höller
Your SOFiSTiK Support Team