PSI - Issue 5

Slobodanka Boljanović et al. / Procedia Structural Integrity 5 (2017) 801 – 808 Slobodanka Boljanović, Stevan Maksimović / Structural Integrity Procedia 00 (2017) 000–000

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8

The failure behavior of pin-loaded situations with the through-the-thickness crack are assessed here by taking into account two different corrective functions related to width-diameter ratio (Eqs. (8a) and (8b)), together with Eqs. (3) to (7). The computed number of loading cycles, as a function of crack length, in the case of different height of the lug head and for different lug thickness is plotted in Fig. 5a and b, respectively. The fatigue estimations shown in Fig. 5 indicate that width-diameter ratio, height of the lug head and thickness can significantly affect the residual strength of the pin-loaded lug under cyclic loading. The present research work proposes a computational model/procedure for assessing the residual strength of damaged lug subjected to cyclic loading. A through-the-thickness crack situation is theoretically here examined by employing fracture mechanics based analytical and numerical models. The fatigue life to failure is estimated through the crack growth concept proposed by Huan and Moan. The fatigue behavior of damaged lug is investigated, so that the effect of the lug head is taken into account. In the failure analysis herein performed, a conservative trend of assessments with respect to relevant experimental results shows that the developed model can be employed for a reliable fatigue strength estimation of the pin-loaded lug with through-the-thickness crack at a hole. 4. Conclusions

Acknowledgements

The authors are grateful to the Mathematical Institute of the Serbian Academy of Sciences and Arts and the Ministry of Science and Technological Development, Serbia for the financial support of this scientific research under Grand No. OI174001.

References

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