I am wanting to apply the hot spot stress approach to an offshore jacket structure. This involves find the nominal stress at joint intersections, forces and moments. I am struggling to output the stress time history I need. I want to extract a stress time history to apply stress concentration factors. After this I use rainflow counting then Miners rule to find the fatigue damage and lifetime of the joint.
It is the nominal stress time history I need to extract and am unsure how to go about this. If anyone can help it would be greatly appreciated.
Thanks!
To compute hot spot stress, you don't need to extract the full time history of stress. If the system is linear, a steady state analysis will provide you the "concentration factor", then you can scale and rainflow counting your signal outside the FEM software