Fracture mechanics approach for a partially debonded cylindrical fibre

The mechanical behaviour of the fibre-reinforced composites depends on the properties of the matrix, the fibres and their reciprocal bonding. Degrading effects occurring in such materials under service - such as matrix-fibre detaching (debonding), fibre breaking, matrix cracking - must be taken into account in the safety assessments. In the present paper, the fibre-matrix debonding phenomenon at the fibre-matrix interface is examined through fracture mechanics concepts, since a geometric discontinuity arises at the edge of the debonded zone (between two dissimilar materials) producing a stress singularity. The mixed mode stress-intensity factors are determined, and the effects of the geometrical and mechanical parameters related to matrix and fibres are discussed. (C) 2013 Elsevier Ltd. All rights reserved.