An extended layerwise spectral finite element framework for delamination growth simulation in laminated composite strips. (15th November 2021)

• Record Type: Journal Article
• Authors: Siorikis, D.K.; Rekatsinas, C.S.; Chrysochoidis, N.A.; Saravanos, D.A.
• Is Part Of: Composite structures. Volume 276(2021)
• Publication Date: 2021-11-15
• Subjects: VCCT Virtual Crack Closure Technique -- XCSLT Extended Cubic Spline Layerwise Theory -- SFE Spectral Finite Element -- SERR Strain Energy Release Rate -- FEM Finite Element Method -- DOFs Degrees of Freedom -- XLSFE Extended Layerwise Spectral Finite Element -- DCB Double Cantilever Beam -- ENF End-Notch Flexure -- MMB Mixed-Mode Bending -- DL Discrete Layer -- XLFE Extended Layerwise Finite Element -- GLL Gauss-Lobatto-Legendre; Laminates -- Spectral finite elements -- Layerwise mechanics -- Fracture -- Delamination -- Interlaminar stresses; Composite construction -- Periodicals; Composites -- Périodiques; 624.18
• DOI: 10.1016/j.compstruct.2021.114452
• Languages: English
• ISSNs: 0263-8223

Abstract

Abstract: A computational framework is presented for the delamination propagation analysis in laminated composite strips that combines an extended high-order layerwise model and a spectral finite element with high-order spatial approximation in the plane of the structure. The extended layerwise laminate mechanics approximate the through-thickness fields using Hermite cubic splines, while the discontinuities in displacement induced by a delamination crack are treated as generalized damage degrees of freedom (DOFs). The layerwise mechanics are integrated into a novel spectral strip finite element, which involves integration points collocated with the nodes, thus providing accurate nodal predictions of the interlaminar stresses on the interface and ahead of the delamination crack tip. Strain energy release rate is predicted by adapting the VCCT method to rely exclusively on the damage DOFs. Finally, an iterative solution method is developed that takes advantage of the damaged DOFs to quickly predict the crack propagation without remeshing. The proposed numerical scheme is applied to mode I, II and mixed-mode delamination fracture problems and is validated vs. reference literature solutions, experimental results and standard 2D plane-strain FE models. The numerical results ultimately illustrate the capacity of the present method to provide accurate predictions with moderately coarse meshes and high computational speed.