Mitigation of Ice-Induced Vibrations Using Tuned Mass Dampers on Offshore Structures in Bohai Bay

This paper presents a brief description of the ice-induced vibrations and some vibration mitigation counter-measures for offshore structures in oil exploration of Bohai Bay. The traditional method used to counteract ice-induced vibration is to increase the stiffness of an existing structure, which is not as cost-effective as the addition of supplementary devices. Although supplementary devices cannot change the characteristics of structure, they are easily adjusted and require little maintenance. So it is believed that this kind of method can be used to mitigate ice-induced vibrations of offshore structures. Field observations show that the platforms in Bohai Bay have the strong filter ability and will oscillate at its natural frequency, even under the action of random ice load. The acceleration response of a platform provides the possibility for a tuned mass damper (TMD) to move. In order to check the performance of a TMD and its effect on the overall structural response, a large-scale TMD was designed and manufactured and a series of experiments were conducted in the laboratory.