The Study Of Stress Concentration Factor For Some Typical Joints Of Offshore Platform

Offshore platform jacket structure located in the dangerous areas of water, whichwill be in the wind, waves, ice, earthquake, corrosion and other work environments,under a complex load of cycle fatigue damage. Its commitment to the offshore platformjoints load transfer between the structures, so the service life of the offshore platformoften depends on its ability to maintain the integrity. At the design stage, through the SNcurve approximation method of peak stress is often used toestimate the fatigue life oftubular joints. However, in fracture mechanics to consider the remaining service life ofmarine management structure, we also need to know the expectedcrack path in the stressdistribution.A model is set up with Femap based on an tubular joints of offshore platform.Thin-shell finite element analyses have been conducted for tubular joints, six degrees offreedom constraints and loading. Calculate the stress distribution of the tubular joints in avariety of load based on ABAQUS, especially on the complex geometric modeling—SCFthrough the thickness and around the intersection of the tube. Using the database of finiteelement analysis results, the curve for the SCFs under six loading cases of the intersectioncan be derived, and get the stress distribution trend for offshore platform structure underthe complex environment provides the basic stress analysis method.Finally, the paper pointed out that the shape parametric τ on the managed nodedistribution of the stress concentration factor, by studying the changes of maximum stressthrough the thickness and around the intersection when the shape factor τ changes，which are of great significance for design and research of tubular joints.