A novel sandwich panel made of prepreg flax skins and bamboo core

• Published in: Composites. Part C, Open access Open access, 2020-11, Vol.3, p.100048, Article 100048
• Main Authors: Ávila de Oliveira, Lívia, Coura, Gabriela Luiza Cota, PassaiaTonatto, Maikson Luiz, Panzera, Túlio Hallak, Placet, Vincent, Scarpa, Fabrizio
• Format: Article
• Language: English
• Subjects: Bamboo; Flax fibre; Flexural and shear properties; Mechanics; Physics; Sandwich panel; Thermosetting
• ISSN: 2666-6820; 2666-6820
• DOI: 10.1016/j.jcomc.2020.100048

•The equivalent density is reduced when larger bamboo rings (Ø30 mm) are used.•Ø30 mm bamboo panels lead to superior flexural properties and skin stress.•Ø20 mm bamboo panels lead to superior core shear modulus.•The lower viscosity adhesive increases skin stress, bending and shear properties.•FEA predicts a good match in terms of load versus displacement curves and damages. This work describes the bending and shear mechanical properties of a novel concept of sustainable sandwich panel made from unidirectional prepreg flaxtape skins and bamboo rings as a circular core material. A Design of Experiment (DoE) is used to determine the influence of the bamboo diameter and the type of adhesive bonding between core and skins on the equivalent density, flexural and shear properties of these panels. Numerical analysis are also performed using cohesive surface contacts between skins and bamboo rings to investigate the structural behaviour and failure mechanisms of the sandwich panels. The equivalent density is affected by both factors, with an overall decrease when larger bamboo rings and lower density adhesive are used. Although sandwich panels with the larger bamboo rings as core show superior flexural properties and skin stress, smaller bamboo rings cores shows an increase in the core transverse shear modulus. The physical and mechanical characteristics of the adhesives directly affect the failure mode and the overall structural integrity of the panels. The failure mode of the bamboo-flax sandwich panels: (a) experimental and (b) shape deformation in the numerical model. [Display omitted]