Translating the material fracture resistance into representations in welded tubular structures

This paper presents an approach to integrate a lower-bound material J-R curve into the load-deformation relationship for circular hollow section joints. The lower-bound J-R curve derives from a regression analysis of the experimental data for a wide range of structural steels reported in the literature and follows a linear relationship up to a maximum crack extension of 2.0 mm. The deterioration in the joint strength caused by ductile tearing adheres to a reduction factor based on the crack area. The J-R curve modified load-deformation responses compare closely with reported experimental results for both welded tubular joints and large-scale tubular frames.