An experimental study of the crack displacement and failure modes of graphite epoxyplates, having central cracks at different angles with the loading axis, was conducted. Due to this type of loading arrangement, the material was under mixed-mode loading condition (mode I and mode II). In this investigation, Moire´ Interferometry technique was employed to measure Crack Opening Displacement (COD) and Crack Shearing Displacement (CSD). Detailed studies were performed to investigate the effect of the crack angle on the strength reduction ratio, the damage zone, and the critical stress intensity factors. The comparison between the Linear Elastic Fracture Mechanics (LEFM) solution and the results obtained from this investigation showed a fair agreement between the theoretical data and the experimental ones. This confirms the validity of implementing the LEFM model for this type of materials.

Issue Section:
Technical Papers
Keywords:
carbon fibre reinforced plastics, cracks, crack-edge stress field analysis, fracture mechanics, moire fringes
Topics:
Fracture (Materials), Graphite, Stress, Fracture mechanics, Displacement, Failure, Epoxy adhesives, Epoxy resins, Composite materials, Interferometry, Damage
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