Bonded and stratified assembly techniques are both used in Chaudronnerie Tuyauterie Resin Anticorrosion, CTRA company, to join GFRP (Roving/ Mat) composites. In this paper, an experimental investigation of these two joining methods is presented. Different tests are used for this purpose: tensile and flexion tests are used to study the adherends whereas, Double Cantilever Beam (DCB) and End Notched Flexure (ENF) tests are employed to provide a comprehensive comparison between these joints, ensuring identical thickness for fairness. The investigations demonstrate that mode I fracture energy of the stratified assembly technique is about 1.6 KJ/mm2 compared with 1 KJ/mm2 obtained when Araldite adhesive is used. This difference increases when mode II fracture energy is analyzed and the GIIc given using the stratified assembly (6.5 KJ/mm2) is significantly higher than the GIIc given using Araldite assembly (2 KJ/mm2). Fracture mechanisms are further analyzed using the Digital Image Correlation (DIC) technique to provide deeper insights into the failure modes.
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