Finite Element Model for the Fatigue Analysis of Cracked Tubular T-Jointsunder Complex Loads

摘要

In practice, tubular joints are always subjected to a combination ofaxial loading (AX), in-plane bending (IPB) and out-of-plane bending(OPB), and the initiations of surface crack do not always start at thesaddle or the crown position on the joints. A systematic finite elementmodelling of tubular Y-joint with any surface crack and located at anyposition along the brace-chord intersection was developed andproposed in this paper. The weld details in the model are compatiblewith the American Welding Society (AWS) codes. The contact surfacesare defined on the crack surfaces to avoid the contact between the twosurfaces that may arise due to some loading cases. Along the crack tip,a well-graded finite element meshes are generated to get the stressintensity factors (SIFs). This modelling method is then used to analysethree tubular T-joint specimens. These full-scale specimens had beentested to failure earlier, and they were subjected to IPB only,combination of IPB and OPB, and combination of AX, IPB and OPBrespectively. The numerical results are then compared with theexperimental results based on the Paris’ law equation. The numericaland experimental results demonstrate that the proposed model isconsistent and reliable.