Study of the mechanical behaviour of a macroscopic glass–polyester composite by ESPI method and numerical simulations

This paper presents results of an experimental and numerical investigation concerning the mechanical behaviour of macromodels for fibre-reinforced composites. Cubic specimens containing an increasing number of glass fibres in a polyester matrix have been produced; the specimens have a 30 mm long side and the fibres a 2 mm long diameter. The displacement field on the surface orthogonal to the fibre direction has been experimentally determined by means of the non-destructive electronic speckle pattern interferometry (ESPI) method for specimens subject to transversal compression. The experimental results have been compared with those of numerical finite element (FE) simulations. The quality of the experimental results and their agreement with the numerical analyses show that the use of macromodels combined with ESPI method could be a valuable guide for a deeper understanding of the mechanical behaviour of heterogeneous materials and for the formulation of models.