Ductile behaviour of carbon steel for welded structures: Experiments and numerical simulations. (September 2020)

• Record Type: Journal Article
• Authors: Tsutsumi, S.; Kitamura, T.; Fincato, R.
• Is Part Of: Journal of constructional steel research. Volume 172(2020)
• Publication Date: 2020-09
• Subjects: Ductile damage -- SM490Y carbon steel -- Mohr–Coulomb criterion -- Stress triaxiality -- Lode angle; Steel, Structural -- Periodicals; Building, Iron and steel -- Periodicals; Acier de construction -- Périodiques; Construction métallique -- Périodiques; 624.1821
• DOI: 10.1016/j.jcsr.2020.106185
• Languages: English
• ISSNs: 0143-974X

Abstract

Abstract: This paper presents an elastoplastic/damage model that couples the constitutive equations of the extended subloading surface plasticity theory with a scalar isotropic ductile damage variable in the continuum damage mechanics framework. The model has previously been applied to Q460 construction steel bars and plates but has not been considered for application to SM steels, which are particularly used in welded structures. The Mohr–Coulomb (MC) fracture criterion was adopted to describe the damage evolution in SM490Y carbon steel. This criterion has been successfully applied to rock and soil mechanics because it can consider the effect of the hydrostatic pressure and Lode angle parameter, which are particularly relevant for this type of material. These two parameters also control the failure of metallic materials, so the field of application for the MC criterion can be extended. Experimental tests were carried out on notched bars and flat grooved plates under monotonic extension to characterize the fracture surface under different values of the stress triaxiality and Lode angle parameter. The results were used to calibrate and validate the numerical model's ability to describe ductile damage. Highlights: Coupled elastoplastic–damage model to predict ductile damage behaviour of steel for weld structures. Damage evolution was evaluated with a modified Mohr–Coulomb criterion. Monotonic tensile tests were done to characterize the strain to fracture envelope. The numerical and experimental results showed good agreement.