Suitability of Various Loads and Structural Response Methods for Fatigue Analysis: A Comparative Study in Arabian Gulf Region

Abstract

Abstract In shallow and intermediate seas, jackets and towers often support offshore facilities like oil and gas platforms and wind turbine foundations. Additionally, these formations may exist in deeper seas. They are tubular-element lattice structures with vertical or slanting legs and tubular bracing. Offshore jackets are susceptible to fatigue due to cyclic wave produced by wave-induced forces and high number of welded tubular connections. These two aspects contribute to the sensitivity to fatigue of offshore lattice structures. For the successful design of offshore constructions, fatigue damage is a crucial limit state criteria since materials with greater static strength must now be used. Historically, the aviation sector was the first to use fatigue as a design criterion, followed by nuclear, steel, offshore, and marine industries. In the latter case, the fatigue limit state (FLS) must be established explicitly due to the use of higher strength steels in the design. Typically, S-N data are derived from laboratory studies, which serve as the foundation for fatigue failure design requirements. The concept selection step for field development necessitates the consideration of a thorough approach to assess the historical and prospective fatigue damage of an existing Offshore jacket structure. It is imperative to ensure that the chosen procedure is highly rigorous due to the significant financial ramifications involved.