Analysis of the effects of free-length on bonded T-joints by an elastoplastic meshless analysis

ABSTRACT

Various configurations of adhesive joints exist, each with unique characteristics. In the case of peel load solicitations, T-joints are the most common choice but are not sufficiently addressed in the literature, especially regarding the geometrical and material influence on their performance. Recently, meshless methods, like the Radial Point Interpolation Method (RPIM), have been used as alternatives to the Finite Element Method (FEM) for investigating joint behaviours. The present work aims to study the free length (FL) effect in T-joints, which is related to substrate stiffness. Three distinct FL dimensions were evaluated. At the same time, the effect of t_p2 and adhesive type were taken into account. Initially, joint strength (P_max) was predicted using two numerical approaches: FEM and RPIM, both employing elastic-plastic material models. Subsequently, the results were compared with the experimental data. Moreover, two yield criteria were considered to analyse the adhesive: von Mises and the Exponential Drucker-Prager criteria. The data resultant from this first phase was then used to select the correct yield criterion for evaluating the influence of FL in the adhesive joints. The methodology was validated, and then geometrical and material design recommendations were presented for the efficient use of T-joints in structural applications.

KEYWORDS:

• Epoxy/epoxides
• polyurethane
• aluminium and alloys
• T-joints
• numerical analysis
• meshless methods

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

The authors thank the following institutions for the funding provided. The Ministério da Ciência, Tecnologia e Ensino Superior through the Fundação para a Ciência e a Tecnologia (from Portugal), under project fundings ‘[POCI-01-0145-FEDER-028351]’, ‘[SFRH/BD/147628/2019]’, and ‘[SFRH/BD/13841/2022]’. Additionally, the authors acknowledge the funding provided by the Associated Laboratory for Energy, Transports and Aeronautics (LAETA), under project0 [UIDB/50022/2020].