Abstract: The stress concentrations in offshore structures usually occur at the intersections of tubular members. For some joints, the stress concentration can produce a maximum stress at the intersection as high as thirty times the nominal stress acting in the members. Stress concentrations aggravate the fatigue of tubular joints in many existing offshore structures. For this reason, accurate computation of stress concentration is very important in tubular joints design. A new study of tubular joints was presented. They were subjected to Combined loading (Com): Axial (Ax) and rotational bending “combined bending (CB)” loading since a lot of studies already done for the joints subjected to one or two of the three types of loading applied to the tubular joints: “in-plane bending (IPB), out-of-plane bending (OPB) and Ax loading”.

Key words: Stress concentration, Offshore structures, FEM, Welded tubular joint