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**Validation of the state-space model of fatigue crack growth in ductile alloys under variable-amplitude load via comparison of the crack-opening stress data.**
*(English)*
Zbl 1196.74250

Summary: This paper presents improvements to the state-space model, through enhancements in the calculations of the constraint factor. These improvements are similar to the calculation procedure of the constraint factor in FASTRAN-II model, which has been extensively validated. The model predictions are compared to various crack growth data as well as FASTRAN-II predictions. Heather to, the state-space model has only been validated through the crack-length data but this paper presents the validation of the state-space model via comparison of the experimental crack-opening stress and crack-length data, thus involving both the states of the state-space model in experimental validation of the model. The experimental data are also compared to the crack-opening stress in FASTRAN-II predictions. Simulation results validate the modeling method of treating the crack-opening stress as a state variable or internal variable. The state-space model considerably reduces the computational complexity of the fatigue crack growth model under variable-amplitude load.

### MSC:

74R20 | Anelastic fracture and damage |

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\textit{R. Patankar} and \textit{R. Qu}, Int. J. Fract. 131, No. 4, 337--349 (2005; Zbl 1196.74250)

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### References:

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