Evolution of the stress intensity factor for patched crack with bonded hygrothermal aged composite repair

The finite element method is carried out to analyse the evolution of the stress intensity factor for cracks repaired with bonded hygrothermal aged composite patches. It is well known that the mechanical characteristics of a laminated composite diminish with the conditioning. In this paper, we use an analytical formula which gives the Young modulus of matrix according to the temperature and moisture. We deduces the values of mechanical characteristics of the laminated composite with the proposed formulas. In the first time, we shown that the mechanical characteristics of the aged laminated composite have a linear behaviour of temperature and moisture. In the second time, we analyse the effects of the aged composite on the stress intensity factor for cracks and its evolution according to the environmental conditions.