Application of continuum decohesive finite element to progressive failure analysis of composite materials. (15th March 2019)

• Record Type: Journal Article
• Authors: Lin, Shiyao; Nguyen, Nhung; Waas, Anthony M.
• Is Part Of: Composite structures. Volume 212(2019)
• Page Start: 365
• Page End: 380
• Publication Date: 2019-03-15
• Subjects: Progressive failure analysis -- Representative volume element -- Delamination toughness test -- Mixed mode law; Composite construction -- Periodicals; Composites -- Périodiques; 624.18
• DOI: 10.1016/j.compstruct.2019.01.021
• Languages: English
• ISSNs: 0263-8223

Abstract

Abstract: The continuum decohesive finite element (CDFE) is a novel finite element technique combining continuum and cohesive crack modeling seamlessly. In CDFE, the transition from a continuum to non-continuum is modeled physically by introducing pairs of dummy nodes to account for the crack separations. A static condensation algorithm is applied to solve for and preserve the separations. In this paper, CDFE has firstly been applied to the modeling of transverse crack growth in a representative volume element (RVE) of composite materials. Microscopic cracks initiate separately and coalesce into a macroscopic transverse crack. In this case, mode I cracking is dominant and the maximum principal stress criterion is used for crack angles. The second problem set is the delamination toughness tests, including a double cantilever beam (DCB) test, an end notched flexure (ENF) test and mixed mode bending (MMB) tests of three mixed mode ratios. In these cases, the crack plane is well-defined and mode mixity is encountered. For better numerical stability, the CDFE inner-element discretization scheme is modified and a novel mixed mode cohesive formulation is implemented. Through analyses, the capability of CDFE to deal with general progressive failure problems of composite materials is shown.