Application Of ETMD In Vibration Control Of Offshore Platforms

Extended turned mass damper (ETMD) vibration control system is an extension of turned mass damper (TMD). It uses the equipment set on the structure instead of additional mass to control the vibration of structures. The theory analysis showed that the frequency range is enlarged and the resonant band is reduced with the mass ratio of ETMD's mass to the residual structure increasing. The FEM simulation showed that the ETMD vibration control system could absorb more vibration energy when the ETMD's frequency is near the excitation frequency. The platform has the better vibration control effect when the mass ratio between 3.75 and 5 and when the frequency ration in (0.3,0.35) and (0.35,5). The whole system, including the platform and the ETMD, has the smaller vibration response when the frequency ratio between 0.5 and 2. The results of the simulation also showed that the ETMD has a better vibration control effect on the traditional jacket platform