Mechanical properties of reinforced composite materials under uniaxial and planar tension loading regimes measured using a non-contact optical method

This study reports the hyperelastic material behaviour of a commercially available PVC/nitrile elastomer with woven continuous nylon reinforcement composite sheet under loading cases of uniaxial extension and pure shear achieved via wide strip tension testing. Through the novel use of an advanced non-contact optical strain measurement technique, the hyperelastic material behaviour of the composite is investigated, and materials parameters are reported for both the warp and the weft directions of reinforcement fibre alignment. The non-contact technique is used to acquire normal and shear strains at the surface of the composite sheet material when loaded to tensile strains (stretches) of up to 0.25. Directly measured shear strains are compared to those derived from the normal strain outputs of an optical rectangular strain rosette array, with both measures showing close agreement. The measured mechanical behaviour under loading is used to determine an approximate strain energy function for the composite via ABAQUS software hyperelastic materials modelling curve fitting, with the Ogden and Yeoh hyperelastic models showing reasonable agreement to experimental data.