Validation of the Dynamic Impact Response of GLARE Laminates and the Role of Strain-Rate Sensitivity: From Conventional to Continuum Shell Modelling

One of the most challenging objectives of modern aeronautics is to constantly ensure flight safety while pursuing increasingly lighter and more efficient structures. To achieve this goal, increasingly accurate simulation models are needed, capable of capturing complex impact phenomena and taking into account a growing number of parameters. In this context, this thesis aims to analyse and validate a numerical approach for predicting the dynamic response to impact of GLARE laminates, with the broader goal of promoting its wider adoption in future aeronautical applications. Validation is pursued both at the macroscopic level, in terms of dent depth, a key indicator of visible damage on the surface, and at the microscopic level, through the analysis of delamination phenomena. Delamination is a recurring phenomenon in laminated composites which, in most cases, has critical effects on structural integrity. However, in specific situations it can also contribute positively by dissipating energy during impact. In any case, its accurate prediction remains essential to ensure safety and certification. A central aspect of this research is the role of strain rate sensitivity, a parameter that has not yet been fully explored in the aerospace industry. In this work, the effects of strain rate are implemented not only in the metallic constituents of GLARE (e.g., aluminium layers) to capture their deformation behaviour more realistically, but also in the cohesive elements between layers. This dual approach allows strain rate sensitivity to influence both the plastic response of the metal and the assessment of delamination, providing a more comprehensive and reliable framework for predicting impact-induced damage. Ultimately, this thesis provides a validated numerical framework that links experimental testing with advanced finite element modelling, representing a step forward toward the reliable and wider adoption of GLARE laminates in future aeronautical structures.