Experimental and numerical studies of initial cracking in CFRP cross-ply laminates Academic Article uri icon

abstract

  • © 2014 Elsevier Ltd. This work is concerned with the conditions for formation of the first (initial) cracks in composite laminates with cutouts or ply drop-offs subjected to in-plane loading. We study here the crack formation on the free edge of CFRP cross-ply laminates experimentally and by numerical stress and failure analysis. The free-edge surface strains are measured by the digital image correlation (DIC) technique. The numerical analysis consists of a two-scale approach, where the macro-level analysis is performed with a three-dimensional finite-element method (3D FEM) and the micro-level analysis uses a periodic unit-cell (PUC) in the transverse plies. The constitutive assumption made for the macro-level analysis is an orthotropic linear thermo-elastic solid for the unidirectional plies with a thin isotropic viscoplastic layer between the longitudinal and transverse plies. In the PUC, the fibers are assumed linear elastic, while the matrix is modeled as an elastic-viscoplastic solid. Crack formation is assumed to occur in the matrix by the dilatation induced brittle failure mechanism for which the dilatation energy density criterion is used.

published proceedings

  • Composites Part A: Applied Science and Manufacturing

author list (cited authors)

  • Okabe, T., Imamura, H., Sato, Y., Higuchi, R., Koyanagi, J., & Talreja, R

citation count

  • 31

complete list of authors

  • Okabe, T||Imamura, H||Sato, Y||Higuchi, R||Koyanagi, J||Talreja, R

publication date

  • January 2015