The effect of laminate sequences on tuft bridging in GFRP laminates under tensile loading

This conference paper reports the tuft bridging behaviour of a single tuft when used in an orthotropic or a quasi-isotropic laminate. Laminates are subjected to pull-out experiments with a full release film placed in the mid-layer of laminates. The force-separation diagrams and damaged samples obtained by tensile tests are analysed to compare two different laminate. The results show that the larger amount of resin present around the tuft in orthotropic laminate reduces by 60% the ultimate tensile strength of the tuft when compared to quasi-isotropic laminates. The tuft tends to fail in the mid-layer of quasi-isotropic laminate with no pull-out, while the tuft has a bit pulling out in orthotropic laminate, causing an increase in the fracture energy.