Composite Materials Research Progress

204
Conclusion
Giangiacomo Minak and Andrea Zucchelli
In this chapter, a new approach to the evaluation of damage progression and of the residual
strength of CFRP was presented.
This approach is based on standard parametric AE and in particular on the acoustic
energy.
A function of the acoustic energy and of the strain energy, called Sentry function, was
introduced and its application was illustrated in the case of:
1) damage progression in tensile testing of different types of CFRP laminates;
2) damage progression and residual strength evaluation in the case of CFRP plates loaded
at the centre.
In the first case, the Sentry function allowed us to single out important material failures
and to calculate the corresponding damage values, while in the second case, after the damage
identification phase, the residual tensile strength was related to the integral of the Sentry
function over the acoustic domain defined in the transversal load test.
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