Analysis of strain distribution in overmatching V groove weld using digital image correlation

Abstract

Welded joints are treated as critical sites when constructing and calculating welded structures due to inhomogeneity and anisotropy of materials at the welded joint site. Because of the change in the geometry of the elements, the welded joint is viewed as the location of the stress concentration and therefore as a place that weakens the overall load capacity of the structure. Due to this approach in the design of welded structures, practice requires that in most cases welded joints are performed with better mechanical properties compared to the base metal. A welded joint that is made so that the mechanical properties of the weld metal exceed the mechanical properties of the base metal is called the overmatching welded joint. This paper presents the measurement of the strain over the ‘overmatching’ welded V joint using the DIC (Digital Image Correlation) method and the analysis of the strain distribution is provided. The strain distribution obtained is interesting because it shows that in the stress concentration points the strain have almost minimal values.