Fracture locus of a Cor-ten weathering steel: Experimental–numerical calibration

Cor-Ten is a weathering steel exploited in the last decade for several applications such as bridges, artworks, building facades, etc. Besides a good strength, it naturally oxides creating a protective layer. This oxide, unlike rust, has the same specific volume of the pure metal. This characteristic allows overcoming the need of protecting treatments like galvanization, etc. While its properties promote its exploitation in civil applications, there are also some examples of application where safety is a fundamental requirement. In the northern part of Italy, Cor-Ten is used for safety barriers (guard rails) along the highways. It is, therefore, fundamental to know the ductile behavior of this material, for which few data are available in literature. Quasi-static experimental tensile tests have been performed on eight samples having different shapes. Numerical simulations carried out with an open-source code (Code_Aster) reproduced the experimental setup. In this way, it was possible to calculate the stress state and the plastic strain at failure needed for the calibration of the ductile damage model. The material model is based on classical incremental plastic response with isotropic hardening and phenomenological concept of damage.