Meso-scale finite element investigation into the short and long term strengths of glass fibre reinforced composites

A finite element model is proposed for simulating the short and long term strength of Glass Fibre Reinforced Plastics. The essence of the model is a division of the composite system into a binary system comprising 'fibre elements' to represent the fibres, and 'effective medium' elements to represent the matrix material, which account for other mechanical properties such as shear and transverse stiffness and Poisson's effect. Such a representation stems from the fact that the performance of a composite material is intrinsically controlled by the microstructure of the component materials. Besides, it has the advantage of the power and versatility of the finite element technique. Typical results for short and long term strengths are compared to similar predictions obtained from shear lag theory. Good agreement is obtained for a variety of finite element discretisations.