Abstract
An experimental apparatus utilizing double cantilever beam specimens loaded with uneven bending moments was developed to study the mixed-mode fatigue crack growth in composites. The approach is suitable when large-scale bridging of cracks is present. To illustrate the testing method, cyclic growth of delaminations in a typical fibre-reinforced polymer composite was investigated under a constant cyclic loading amplitude. Pure mode I, mode II and mixed-mode crack growth conditions were examined. The results, analysed using a J-integral approach, show that the double cantilever beam loaded with uneven bending moments configuration provides a robust approach to investigate the fatigue crack growth of composites for pure mode and mixed-mode cracking. A steady-state crack growth regime was observed for mode I and mixed-mode loading. For mode II loading, steady-state was absent, and a progressively decreasing crack growth rate observed. In addition to details concerning the equipment, a general discussion of the development of cyclic bridging laws for delamination growth in the presence of large-scale bridging is provided.
Original language | English |
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Pages (from-to) | 3111-3128 |
Number of pages | 18 |
Journal | Journal of Composite Materials |
Volume | 48 |
Issue number | 25 |
DOIs | |
Publication status | Published - 1 Oct 2014 |
Externally published | Yes |
Keywords
- Polymer-matrix composites
- delamination
- fatigue
- large-scale bridging
- mechanical testing
- mixed-mode loading