الفهرس 
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Abstract
Fixed offshore platforms are widely spreaded all over the world. They are constructed since 1960s or before. In fact, these types of structures are planned to be in life only for 20 to 25 years until the oil reservoir be fully drained. However, in many field areas the oil reservoir under platforms was discovered that it has over estimate potential, which presence a need to extend the life of the offshore platform for several additional years. As a result of this, proper strengthening is required to overcome the deterioration may be occurred in the structure members or the changed environmental loading may be new. Because the dynamic loads are considered the main loading in the fixed offshore platforms, a special interest is introduced in this research for the mitigation of this structure type against dynamic loads. Far from the traditional methods for strengthening, this research concentrates on how to make use of the energy dissipation devices, as a smart solution, to increase the fixed platforms lateral resistance. The challenge in using the energy dissipation devices, lie on its ability to increase structure lateral resistance without increasing structure masses. Friction damping device is studied in this research in detail and its application to the fixed offshore platform is presented analytically. A friction damper device is manufactured locally in a primitive manner using the available materials in the local market in Egypt and an experimental work is performed in the laboratory using shaking table test. The friction damper is tested through a simple steel frame and the test results are extracted. from the obtained experimental results, a chosen mathematical theory is used to simulate the friction damper behavior. The mathematical simulation of the damper is assessed using finite element model and verified in conjunction with the executed experimental work. Finally, a case study is presented for a fixed offshore platform to show the value of applying friction damper in increasing the lateral resistance under wind, waves and currents. At the end, some ideas are presented to be future studies in this research subject.
Key words: Offshore structures; Dynamic loads; Energy dissipation devices; Damper; Experimental; Finite element.