198. isogeometric analysis for the prediction of the damage growth in composite laminates
Name: Marco Simone Pigazzini
Grad Year: 2017
Composite materials have become increasingly popular in the past decades for high-performance and lightweight applications. An accurate assessment of the damage condition is considered a crucial factor for the development of damage-tolerant composite structures. While numerical analysis plays a primary role in the prediction of the damage propagation, the inherently complex damage mechanisms of composite materials pose several challenges in the development of computationally efficient and reliable technologies for damage analysis. The concept of the Isogeometric Analysis (IGA), which was originally developed to bridge the gap between the Computational Aided Design (CAD) technology and the computational mechanics, allows to ease the transition from the geometrical modeling to the structural analysis by performing numerical simulations directly on high fidelity CAD models. A multi-layered modeling approach is proposed in the framework of the IGA. It consists in the representation of the composite laminates at the level of the individual plies, or group of similar plies, connected through cohesive interfaces which aim to enforce the continuity of the displacements. The novel cohesive interface formulation, which is specifically developed to be used in combination with the Kirchhoff-Love shell elements, is then equipped with a cohesive damage model in order to predict the onset and the propagation of the delamination front. The intralaminar elasto-plastic damage response and the in-plane damage modes related to tension, compression and shear, are also included, and evaluated layer by layer at the level of each ply. The modeling approach is validated through the correlation with a series of experimental test from the literature. The higher-order continuity of the NURBS shape functions translates into a better representation of the strains, which drive the intralaminar damage model, and of the displacement jumps in the area of the delamination front, which drive the cohesive damage model. This allows to adopt a coarser discretization of the structure and a larger integration time-step, without compromising the stability of the analysis. It is found that the proposed modeling approach is a computationally efficient and accurate analysis tool that can be effectively adopted for the simulation of full-scale composite components.
Industry Application Area(s)
Aerospace, Defense, Security | Civil/Structural Engineering