The mechanical performance of H-shaped NCF adhesively bonded joints

Adhesive bonding is contemplated as an alternative method to mechanical fastening for joining composite aerostructures.

Ongoing research in this area is focused on the development of new bonding techniques and joining elements. In this

article, the mechanical performance of the novel noncrimp fabric (NCF) H-shaped adhesively bonded joints subjected to

tension, shear and four-point bending loading conditions was investigated by both experimental tests and numerical

modeling. The H profiles were manufactured by employing the preforming and injection molding methods, while bonding

of the assembled parts was carried out using a novel stepwise procedure which leads to a high bonding quality.

Investigation was conducted by means of mechanical testing and a mesomechanical model based on the FE method

and the progressive damage modeling approach. In the model, both adhesive failure (debonding) and failure of the NCF

material is considered. In the tension and shear load cases, the joint failed due to extensive debonding attributed to

adhesive shearing, while in the four-point bending load case, due to failure of the H element. In all three load cases, the

experimental and numerical results compare well thus, providing establishment of the numerical model in simulating the

performance of textile structural parts. Finally, the effort presented herein is rated as successful since new adhesive

bonded joints of high mechanical performance are proposed.

Ahead of print in the Journal of Composite Materials