Modelling through-thickness and surface cracks in tubular joints

摘要

This paper describes the geometrical modelling, finite element mesh generation and estimation of stress intensity factors of T-joint and Y-joint containing through-thickness or surface cracks. It enables cracks of any length to be located at any point along the intersection between the weld toe and the chord member. This is particularly significant as it is found in practice that the initiation site of a surface crack does not always start from the saddle or crown position when these tubular joints are subjected to a combination of axial, in-plane and out-of-plane loading. One typical T-joint containing a surface semi-elliptical crack at the saddle position has been analyzed using this new modelling approach, and the results are used to evaluate the stress intensity factor (SIF) of the crack. The SIF validation results demonstrate that the model is reliable.