On three-dimensional fibrous flaws in unidirectional fibre reinforced elastic composites

This paper examines the problem of the stress concentration at a flaw in a unidirectional fibre reinforced composite. The geometry of the flaw corresponds to a spheroidal region in which the reinforcing fibres exhibit continuity across the flaw surface. The composite containing the flaw is subjected to a uniaxial stress field which acts along the fibre direction. An exact solution is devoloped for the stress concentration factor at the reinforced flaw boundary. Typical numerical results presented in the paper illustrate the manner in which the stress concentration at the bridged flaw is influenced by the fibre volume fraction, the fibre-matrix modular ratio and the flaw geometry.