Mode I intralaminar fracture toughness of 2D woven carbon fibre reinforced composites: A comparison of stable and unstable crack propagation techniques

•We performed intralaminar fracture toughness tests on 2D woven CFRP composites.•We compared stable and unstable crack propagation techniques.•We numerically calculated the SIFs for the investigated geometries.•We determined the intralaminar fracture toughness using the size effect method.•We numerically replicated the experiments by using computational mechanics. This paper presents an experimental and numerical comparison of stable and unstable crack propagation techniques used to measure the mode I intralaminar fracture toughness of 2D woven carbon fibre composites. Compact Tension (CT) and Double Edge Notch Tension (DENT) specimens are used for the stable and unstable experimental tests, respectively. The precrack tip radius sensitivity of the scaled DENT specimens is investigated, concluding that the tested tip radii do not substantially affect the measured fracture toughness. The fracture toughness data obtained from the DENT and CT specimens are found to be in good agreement for both tested materials.