Holistic determination of physical fracture toughness values and numerical parameters for delamination analysis considering multidirectional-interfaces

Delaminations are a concern for the structural integrity of fibre composite structures. The decisive material parameter delaminations is fracture toughness. Structures usually have multidirectional ply stacking. However, interface orientation dependant toughness values and R-curve effects neglected in numerical delamination analysis. This work investigates specific considers mode I to improve simulation accuracy. Therefore, I, II mixed different orientations determined experimentally verified using analysis characterisation specimens with cohesive zone modelling. In this way, an engineering methodology provided experimental comprehensive modelling mesoscale progressive damage addition, full set four interfaces M21-T700GC prepreg given. It can be shown that use standard 0°//0°-values leads very conservative results. increases Ultrasonic scans DCB used compare crack front shapes validation. Not only load displacement curves well captured, but also shapes. demonstrates by smearing microscale effects, behaviour captured phenomenologically correct suitable industrial use.