Use of localized necking and fracture as a failure criterion in ship collision analysis. (September 2020)

• Record Type: Journal Article
• Authors: Cerik, Burak Can; Park, Sung-Ju; Choung, Joonmo
• Is Part Of: Marine structures. Volume 73(2020)
• Publication Date: 2020-09
• Subjects: Localized necking -- Ductile fracture -- Shell element -- Fracture modeling -- Ship collision -- Accidental limit state; Naval architecture -- Periodicals; Offshore structures -- Periodicals; Architecture navale -- Périodiques; Structures offshore -- Périodiques; Naval architecture; Offshore structures; Periodicals; 620.4162
• DOI: 10.1016/j.marstruc.2020.102787
• Languages: English
• ISSNs: 0951-8339

Abstract

Abstract: This study explores the use of localized necking for failure modeling in maritime crash analysis, using large shell elements. The assumption that the failure of a large shell element occurs simultaneously with the onset of localized necking is revisited. This study particularly investigates the numerical implementation of the localized necking condition and its implications on the results of ship collision analysis involving not only plate rupture but also various failure mechanisms such as the crushing and tearing of web girders, stringers, and their intersections. Through a series of large-scale collision simulations, the effects of bending deformation on the initiation of necking, non-proportional loading paths, and ductile fractures not preceded by localized necking, are investigated. It is demonstrated that a localized necking-based fracture model provides a reasonable, relatively mesh-insensitive estimate of the onset of fracture in the outer hull panels; however, fracture propagation is very sensitive to the numerical implementation of the necking and fracture model, especially for the cases involving the crushing of web frames and stringers. Highlights: Failure of stiffening members, web frames and girders significantly affects rupture of plating. Fracture propagation is highly sensitive to the numerical implementation of necking as failure condition. Necking modeling based on forming severity concept provides physically more consistent results. Fracture without localized necking are observed in web-stringer crushing simulations.