VIBRATION MITIGATION OF STRUCTURES IN THE MARINE-ENVIRONMENT

The research described in this paper involves a method to mitigate the vibration of an offshore structural system in the marine environment when subjected to the in-plane wave forces. The method introduced incl ude a practical application for the viscoelastic material to the offsh ore structural system, and the analytical technique to evaluate the st ructural responses when the system is incorporated with damping device s. The viscoelastic materials applied here were tested and verified th at they have high energy absorption capacity. In the analysis, the app lied wave forces are based on the fifth-order Stokes wave theory and M orrison equation for small body and the computation method is based on Newmark method for nonlinear system. Results of the vibration respons es for the system with added damping devices are presented and compare d to the responses of structures of the traditional design. It was obs erved that the effect of the vibration mitigation was significant and the dynamic performance of the offshore structural system were greatly improved when the new damping devices were applied. Copyright (C) 199 6 Elsevier Science Ltd