Measurement of the in situ ply fracture toughness associated with mode I fibre tensile failure in FRP. Part I: Data reduction

The fracture toughness associated with fibre tensile failure was measured for a T300/920 laminated carbon/epoxy material system using the compact tension specimen configuration. Six methods of data reduction were investigated for calculation of the toughness with the aim of finding the best technique, in terms of reproducibility of results and simplicity. The calculated fracture toughnesses were found to correlate well, though varying amounts of scatter were produced by each method. An optimum method was proposed that does not rely on the use of an optically measured crack length.