Identification of Behaviour Laws and Failure Criteria Parameters of Composites Based on Off Axes Tests Application: Composite Polyester/Alfa

摘要

The purpose of the present study is to propose a method for identifying the mechanical behaviour of composite materials based on off axes tests for various directions, in a more general framework including a large range of geometrical variables used in industry. We propose a mechanism based mode which strongly depends on the structural anisotropy of the material and on the orientation of loading. For failure we use a quadratic surface similar to Hill criterion, the coefficients of which depend on the type and the direction of loading. The proposed identification method is applied to a composite made out of woven vegetal fibres and a polyester resin matrix. The fibres are extracted from Alfa leaves which are abundant in North Africa, and are commonly used in the manufacturing of high quality paper.