AbstractIn this master thesis we study a corner detail between a deck and bulkhead plate, located inside asemi submersible platform. The platform structure is made from steel components such as plates,stiffeners, girders, and brackets. The deck is supported by paralel beams which ae supported oncolumns that are connected to the bulkhead. The corner detail, where the beam comes across thecolumn, is often exposed to high stresses that can be critical for both the capacity and fatigue lifeof the structure. A common way of improving this detail is by using brackets, stiffeners andthicker plates.The intention of the thesis is to analyse different shapes of the corner detail, and to determinewhich one has the largest capacity and best fatigue resistance. Due to the complex geometry ofthe corner detail, analytical solutions are difficult to find and it is convenient to apply finiteelement method to obtain the results. Linear elastic theory is used to determine the stressconcentration factor and estimate the fatigue life of the structure, for the different types of loadcases. A buckling analysis is utilized to determine the first five eigen values, which are furtherused to introduce an initial shape deflection in the non linear analysis. Three different models ofthe corner detail, based on Aker Solutions standard details, are created and analyzed. For eachdetail, different boundary conditions and load cases are applied, in the finite element methodsoftware Abaqus. The best model is determined by comparing the results from both the linear andnon linear analysis, for every load case, for all three models. Results from the non linear analysisare also compared with hand calculations, in cases where this is possible, while results from thelinear analysis are verified by comparison with results for similar details found in literature.Based on the results from these three models, a modification of the corner detail is presented andanalyzed in Abaqus with the same boundary conditions and load cases as earlier. The mainintention of the modification is to improve the capacity of the detail. The final analysis results arecompared with the former three models.