Development of a numerical methodology for the analysis of the post-buckling and failure behavior of butt-joint stiffened thermoplastic composite panels

• Published in: Engineering failure analysis 2024-06, Vol.160, p.108193, Article 108193
• Main Authors: Psihoyos, Harry, Fotopoulos, Konstantinos, Lampeas, George, Waleson, Jan, Brethouwer, Michel, Romano, Brendan, Pearson, Derrick
• Format: Article
• Language: English
• Subjects: Butt-joint; Composite panel; Failure analysis; Finite element modelling; Post-buckling
• ISSN: 1350-6307; 1873-1961
• DOI: 10.1016/j.engfailanal.2024.108193

•The presentation of a numerical finite element modelling and simulation methodology for the analysis of butt-joint stiffened thermoplastic composite panels.•A combined nonlinear progressive damage modelling (PDM) and cohesive damage modelling (CZM) approach is employed for the analysis of the buckling and the failure behavior of panels.•The methodology is applied for the analysis of two butt-joint stiffened AS4D/PEKK-FC panels, on in pristine condition and the other with an Barely Visible Initial Damage (BVID).•Debonding between the stringers and the skin is the main failure mechanism in both experiment and simulation.•The comparison between experimental and numerical results showcase that the buckling modes and the main failure mechanism of the panels can sufficiently be predicted by the methodology.•The methodology can be used for the analysis and design of butt-joint stiffened composite structures. This paper presents the development of a finite element (FE) numerical modelling methodology for the post-buckling and failure analysis of butt-joint stiffened thermoplastic composite panels. The structural components of the investigated panels are bonded with co-consolidated butt-joint methods - a novel joining technique used in aerospace structures. Two panels are examined in this work: the first in pristine condition and the second with a pre-inflicted damage, to evaluate the influence of the damage on the mechanical response of the panel. To assess the ability of these panels to operate safely in the post-buckling region, the nonlinear FE methodology employs large displacement analysis, progressive damage modelling (PDM) and cohesive zone modelling (CZM) approaches. The focuses are placed on the prediction of the displacement fields, the intra-/inter-laminar failure and the debonding between the components of the panel. For validation purposes, the simulation results are compared with the available experimental measurements. The correlation demonstrates the ability of the developed methodology for the modelling and simulation of panels with the same structural configuration.