PSI - Issue 18

Roberta Massabò et al. / Procedia Structural Integrity 18 (2019) 484–489 Author name / Structural Integrity Procedia 00 (2019) 000–000

488

5

an important Mode I component (phase angle

in the range shown, with

1 tan ( 

/ ) 61.7 65.3  







II G G

I

0 / 90     for mode I/mode II) so that the assumption of mode II dominant conditions is not satisfied.

Fig. 3. Critical load versus load point displacement in unidirectional ENF fracture specimens, Fig. 2a, tested in (Madhukar and Drzal, 1992).

(a)

(b)

Fig. 4. Dimensionless diagrams of the critical load for crack propagation versus load point displacement in the cantilever beam in Fig. 2b. Comparison between the results of the homogenized model and a discrete-layer model (Andrews and Massabò, 2006).

Fig. 5. Dimensionless diagram of critical load for crack propagation versus crack length in three-point bend beams. Black curves: homogeneous beam, (2) (1) 2 2 1 E E  ; red curves: sandwich beam, (2) (1) 2 2 1 / 4 E E  .