PERFORMANCE EVALUATION OF HYBRID DAMPING SYSTEMS IN OFFSHORE JACKET PLATFORMS

Employing dampers to control wave-induced and seismic vibrations of offshore jacket platforms is an attractive method in order to mitigate external damage. However, adjustable parameters of a damper are designed by considering only one type of environmental loads; either normalcondition load or extreme-condition load. So, it is important to investigate effectiveness of damping system, for both of two main categories of loads. It is ideal for the system to have an acceptable performance in both normal and extreme conditions. The idea investigated in the current study is to use a friction damper device (FDD) and a tuned mass damper (TMD) simultaneously as a hybrid damping system (HDS) for use in offshore jacket platforms with float-over deck. By introducing HDS, it is intended to make damping system have a high seismic performance while being effective in fatigue damage mitigation. HDS can have different combinations. So, certain variants of HDS are determined which have much higher performance than the other variants.

کلیدواژه ها:

Offshore Jacket Platform ، Float-Over Deck ، Wave-Induced Fatigue Damage ، Seismic Load ، Vibration Control ، Friction Damper ، Tuned Mass Damper ، Hybrid Damping System