A micro-mechanics perspective to the invariant-based approach to stiffness

• Type: Article in International Scientific Journal
• Date: 2019

Authors

Arteiro, A (Author) FEUP; Pereira, LF (Author) Other; Bessa, MA (Author) Other; Furtado, C (Author) FEUP; Camanho, PP (Author) FEUP

Journal

Title: Composites Science and Technology

Vol. 176

Pages: 72-80

ISSN: 0266-3538

Publisher: Elsevier

Indexing

ISI Web of Knowledge - 10 Citations

Scopus - 12 Citations

Other information

Authenticus ID: P-00Q-F6N

DOI: 10.1016/j.compscitech.2019.04.002

Abstract (EN): To simplify the analysis and characterisation of composite laminates, an invariant-based approach to stiffness that takes the trace of the plane stress stiffness matrix as a material property was recently proposed. In the present work, a study based on micro-mechanical models brings new insight to this invariant-based approach. The Rule of Mixtures and the Halpin-Tsai models are used to establish the relations between the fibre volume fraction, the fibre/matrix stiffness ratios, and the trace-normalised engineering constants of unidirectional laminae and multidirectional laminates. For sufficiently high longitudinal fibre/matrix stiffness ratios and for fibre volume fractions between 50% and 70%, typical of advanced CFRPs, the variation of the trace-normalised longitudinal Young's modulus is within 6% for unidirectional laminae and within 1% for multidirectional laminates, supporting the definition of an invariant-based approach to stiffness based on a Master Ply concept and laminate factors derived thereof, defining clearly a domain of applicability of the invariant theory and confirming the empirical observations of the past.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 9