Analytical calculation of stress concentrations at welded flange necks

摘要

Ring flange connections for tubular towers, such as those for wind turbines or chimneys, are subjected to significant fatigue loading. Apart from the bolts, it is also necessary to carry out a fatigue analysis of the weld connecting the flange to the tower shell. Owing to the presence of the flange, local bending moments occur in the shell which increase the nominal (membrane) stresses, i. e. stress concentrations occur. This paper presents an analytical model for calculating these local bending moments such that stress concentrations can be determined. The analytical model was compared with results from 3D finite element models, and good agreement was found. The results from the model presented are thus deemed appropriate for design purposes.