PSI - Issue 2_A

F. Musiari et al. / Procedia Structural Integrity 2 (2016) 112–119

115

Author name / Structural Integrity Procedia 00 (2016) 000 – 000

4

Fig. 1 - DCB test of N01 virgin specimen

3.2. Results and discussion Firstly, the results relative to the virgin specimens are presented. Fig. 2 presents a force vs. displacement curve relative to the V01 virgin specimen. The numbers identify the force peaks in correspondence of which the compliance is used to evaluate the crack length.

Fig. 2 - Force vs. Crack Opening Displacement (V01 virgin specimen)

Once that the crack length is known, Mode I fracture toughness for each force peak is calculated through the Krenk model (Krenk, 1992), Eq. 1.

2

1 1        a  

2 2

 bEI G P a

(1)

λ σ is given by the following expression, Eq. 2.

E

6

 



a





(2)

4

3 h t

2

E

1





a