Table 1.

Stress intensity factors (in units of MPa√m) as nominally applied from the far-field load and inferred at the crack tip by fitting LEFM solutions to the strain maps measured mid-thickness at maximum load during a normal cycle and during an overload cycle for an AA 5091 sample [22]. The uncertainties given in the parentheses are 2×standard deviation (95%) confidence limits.

fatigue/overload	applied KnomI	crack tip KeffI	crack tip KeffII
fatigued	6.6	6.11 (0.21)	0.33 (0.53)
100% overload	13.2	13.3 (1.83)	0.71 (0.38)
one cycle after overload	6.6	6.2 (0.46)	−0.06 (1.19)