No abstract

In this paper, a new progressive damage model has been established with the aim of predicting the exural behaviour and damage evolution of different composite laminates under three-point bending. In this proposed model, a progressive failure algorithm is developed for numerical analyses where the intra/interlaminar failure modes were considered for estimating the damage evolution. A set of gradual stiffness degradation rules were proposed to predict further damage evolution following damage initiation estimated by the combination of the three-dimensional Puck failure criteria and the cohesive zone model. The damage mechanics of composite laminates IMS194/CYCOM977-2 with ply sequence and AS4/PEEK with ply sequence are investigated by our proposed model. In addition, the present model's results were compared with those reported in the literature. Our ndings indicate that the proposed model accurately predicts the failure of laminates, which is bene cial to the study of the damage mechanism of composite laminates.these features are di cult to quantify and may not be possible to identify them at all [1]. The collapse of composite structures is part of a progressive degradation process. Furthermore, it is important to note that local failure causes load redistribution, allowing multiple failure mechanisms to emerge, which diminishes the strength of the composite structure, decreases the capacity of carrying the stress, and ultimately leads to global rupture of the composite. Moreover, it is di cult to accurately represent the stiffness behaviour of a bre carbon-reinforced polymer coupon due to numerous interacting aspects, such as treatment techniques, distribution and arrangement of the bres and matrix. On the other hand, exural testing leads to bene cial mechanical parameters for composite laminates, such as exural modulus and shear stress, as well as a better ability to comprehend and describe the cohesive inter-layer interactions. The advantage of three-point bending tests is that they have advantages in terms of specimen generation, they allow progressive tracking of specimen degradation to nal failure, the location of the failure is foreseeable, and they also allow validation of the strength of composite structures. Once a specimen is subjected to a bending load, the three basic stress states of the material are induced, namely tension, compression and shear. The failure of composite material is controlled mainly by one of the three basic stresses that will be the rst to attain its ultimate value. Parallel to this, previous studies of damage composites under bending load have assumed equal compressive and tensile responses, resulting in over-or underestimation of composite resistance. In order to improve the accuracy of the post-processing analysis and reduce effectively time and costs and exploit fully the pro ts of composite structures under different loads, more credible failure theories and damage propagation approaches are urgently required. M. A. Caminero et al [2]have carried out a three-point bending tes...

The purpose of this work aims to assess the failure of an open-hole composite laminate subjected to tensile loading, using different progressive damage approaches. Within Abaqus, a user-defined material subroutine (UMAT) was developed and implemented by applying a combination of Puck’s failure criterion and the gradual degradation model. In addition, the integrated model in Abaqus based on the Hashin failure criteria coupled with the continuous damage model has been also considered. Moreover, the effect of different specimen sizes on the behaviour of the AS4/PEEK composite laminate has been performed. The predicted results were compared to those available in the literature. The results of this comparative study showed good agreement between the experimental outcomes and the numerical predictions.

No abstract

In this paper, a new progressive damage model has been established with the aim of predicting the flexural behaviour and damage evolution of different composite laminates under three-point bending. In this proposed model, a progressive failure algorithm is developed for numerical analyses where the intra/interlaminar failure modes were considered for estimating the damage evolution. A set of gradual stiffness degradation rules were proposed to predict further damage evolution following damage initiation estimated by the combination of the three-dimensional Puck failure criteria and the cohesive zone model. The damage mechanics of composite laminates IMS194/CYCOM977-2 with ply sequence and AS4/PEEK with ply sequence are investigated by our proposed model. In addition, the present model's results were compared with those reported in the literature. Our findings indicate that the proposed model accurately predicts the failure of laminates, which is beneficial to the study of the damage mechanism of composite laminates.