PSI - Issue 41

Victor Rizov et al. / Procedia Structural Integrity 41 (2022) 115–124 Author name / Structural Integrity Procedia 00 (2019) 000 – 000

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in Fig. 4. The curves in Fig. 4 indicate that the non-linear viscoelastic behaviour causes increase of the strain energy release rate. Increase of 11 12 /   ratio reduces the strain energy release rate (Fig. 4). The influence of 11 12 / E E and 11 13 /   ratios on the strain energy release rate is shown in Fig. 5. It can be observed that the strain energy release rate decreases with increasing of these ratios (Fig. 5).

5 0.2 10   

M v (curve 1 – at

F v

Fig. 6. Variation of the non-dimensional strain energy release rate with

N/s, curve 2 – at

5 0.4 10   

5 0.6 10   

F v

F v

N/s and curve 3 – at

N/s).

F v and M v , on the strain energy release rate is illustrated in Fig. 6. One can see F v and M v leads to increase of G . The influence of M v on G is stronger than that of F v (Fig.

The influence of parameters,

that increase of 6). 4. Conclusions

The strain energy release rate for a delamination crack in a twice statically undetermined beam structure is derived. The beam under consideration is multilayered. The layers have non-linear viscoelastic mechanical behaviour. The beam is loaded by bending moment and axial force. The balance of the energy is analyzed to derive the strain energy release rate. For this purpose, first, the static indeterminacy is resolved. The method of the J integral is applied for verification. The strain energy release rate is derived also assuming that the same beam is statically determinate. It is found that the strain energy release rate in the statically undermined beam is lower than that in statically determined one. The analysis indicates that increase of 11 12 /   , 11 12 / E E and 11 13 /   ratios reduces the strain energy release rate. The increase of parameters, F v and M v , causes increase of the strain energy release rate (the effect of M v on the strain energy release rate is stronger that that of F v ). References

Broek, D., 1986. Elementary engineering fracture mechanics. Springer.