TY - GEN
T1 - A time-based formulation for real-time fatigue damage prognosis under variable amplitude loadings
AU - Zhang, Wei
AU - Liu, Yongming
N1 - Funding Information:
The research reported in this paper was supported by funds from Air Force Office of Scientific Research: Young Investigator Program (Contract No. FA9550-11-1-0025, Project Manager: Dr. David Stargel). The support is gratefully acknowledged.
PY - 2013
Y1 - 2013
N2 - A time-based fatigue crack growth algorithm is proposed in this paper to calculate the fatigue crack growth under general random variable amplitude loading. This approach is based on the analytical crack tip opening displacement (CTOD) estimation and a subcycle fatigue crack growth model. The discussion is first given for fatigue cracks without considering the crack closure. Next, the model is extended to the growing crack with the crack closure. Following this, a general fatigue crack growth algorithm is proposed under general random variable loadings, which is combined the crack closure model and the geometrical relationship between the CTOD and the crack increment (da) at any time instant within a cycle. To validate this algorithm, a testing is performed for Al7075-T6 under "Christmas Tree" loading spectra, which cannot be easily handled by the classical cycle-based approaches. The predictions match the experimental data very well. A detailed discussion is given based on the current investigation.
AB - A time-based fatigue crack growth algorithm is proposed in this paper to calculate the fatigue crack growth under general random variable amplitude loading. This approach is based on the analytical crack tip opening displacement (CTOD) estimation and a subcycle fatigue crack growth model. The discussion is first given for fatigue cracks without considering the crack closure. Next, the model is extended to the growing crack with the crack closure. Following this, a general fatigue crack growth algorithm is proposed under general random variable loadings, which is combined the crack closure model and the geometrical relationship between the CTOD and the crack increment (da) at any time instant within a cycle. To validate this algorithm, a testing is performed for Al7075-T6 under "Christmas Tree" loading spectra, which cannot be easily handled by the classical cycle-based approaches. The predictions match the experimental data very well. A detailed discussion is given based on the current investigation.
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U2 - 10.2514/6.2013-1651
DO - 10.2514/6.2013-1651
M3 - Conference contribution
AN - SCOPUS:84880844801
SN - 9781624102233
T3 - 54th AIAA/ASME/ASCE/AHS/ASC Structures, Structural Dynamics, and Materials Conference
BT - 54th AIAA/ASME/ASCE/AHS/ASC Structures, Structural Dynamics and Materials Conference
T2 - 54th AIAA/ASME/ASCE/AHS/ASC Structures, Structural Dynamics and Materials Conference
Y2 - 8 April 2013 through 11 April 2013
ER -