Submerged structures, repair

The first step in the design of fixed structures is the computation of the forces on its members due to the extreme environment present at the site. Forces on the submerged members of the structure arise from currents, and waves. The fatigue life of the members is also of concern in the design of these structures. In fact, several structures have failed due to the fatigue failure of critical members in the structure. It is not uncommon to repair or replace the underwater members of a fixed jacket structure during its lifetime. 

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