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 |
|---|---|
| Journal | Journal of Composite Materials |
| Volume | 48 |
| Issue number | 25 |
| Pages (from-to) | 3111-3128 |
| ISSN | 0021-9983 |
| DOIs | |
| Publication status | Published - 2014 |
Keywords
- Polymer–matrix composites
- Fatigue
- Delamination
- Mixed-mode loading
- Large-scale bridging
- Mechanical testing