Delamination failure of steel single angle sections

Delamination is one of the most important material irregularities which affect the strength of materials under any type of loading. Delamination can be described as the separating of layers from each other or the formation of unconnected layers. Delamination irregularity can be formed during the manufacturing stage of a structural element, service loads and other effects such as corrosion. Delamination in materials is an irregularity which can be formed suddenly (by impact) or slowly over time (by corrosion fatigue). In this study, the delamination effects on single angle sections are examined, which are commonly used in engineering structures because of their geometrical properties. Delaminations are studied in single angle sections under bending and axial loads. After the experiments and examinations, it is concluded that delamination crack width is very effective on the strength of steel single angle section structural members.

► Metalographic specimens are extracted from the possibly delaminated material segments by wet-cutting method and micro-structures of specimens are examined.
► An experiment device is set for examining the behavior of delaminated single angle sections under bending and axial loading.
► This experiment device is chosen to be capable of applying axial load, bending and torsion to test specimens and measuring the strains and deflections precisely.
► It is seen that crack width affects load carrying capacity of the structural elements considerably.
► It is concluded that absence of delamination irregularity must be checked before considering theoretical strengths of materials which are going to be used in structures.