PSI - Issue 25

Victor Rizov / Procedia Structural Integrity 25 (2020) 88–100 Author name / Structural Integrity Procedia 00 (2019) 000 – 000

94

7

stresses.

Fig. 4. Two three-layered cantilever beam configurations with a delamination crack (a) located between layers 2 and 3, and (b) located between layers 1 and 2.

In order to verify the results obtained by using the approach developed in the previous section of the paper, the strain energy release rate is calculated also by differentiating of the strain energy stored in the beam with respect to the delamination crack area

bda G dU  ,

(16)

where da is an elementary increase of the delamination crack length.

Fig. 5. The strain energy release rate in non-dimensional form plotted against the non-dimensional time (curve 1 - for the three-layered beam configuration with a delamination crack between layers 1 and 2, curve 2 - for the three-layered beam configuration with a delamination crack between layers 2 and 3). In order to investigate the effect of the crack location along the beam height on the delamination fracture behaviour of the beam, two three-layered cantilever beam configurations are considered (Fig. 4). The thickness of