In the present study, finite element modelling has been used to examine the stress concentration effects of having a central hole in unidirectional glass fibre-reinforced polyester (GFRP) laminates, under tensile loading. Special focus has been given to the load carrying capacity, in terms of defining an equivalent stress concentration factor (KT), and sample initial stiffness. A virgin model (without a central hole) has been used as a basis for evaluating the stress concentration effects. In addition, progressive failure features, before complete failure, have been modelled with the aid of the multi-continuum theory (MCT). Two ply-orientations were examined; [0/90]2S and [±45]2S laminates. The model was first validated using previously published experimental data. The results were explained in terms of local stress state, compared to simple mechanics of materials basics, and agreed with previously published results. |
