Residual Strength and Fatigue Lifetime of ... - Solid Mechanics

was used to monitor 3D surface displacements and 2D surface strains continuously during the
experiments. The DIC camera position and the test rig are seen in Figure 3.10. A ramp
displacement controlled loading with a rate of 1 mm/min was applied in all tests. A sample rate
of one image per second was used for the DIC measurements. The DIC system was used to
measure the initial imperfection in the surface of the panels. Figure 3.11 shows the initial
imperfection measurement for a panel with H130 core and a debond diameter of 200 mm.
(a) (b)
Figure 3.10: (a) Test rig and (b) test setup.
Figure 3.11: Initial imperfection from DIC measurements in a panel with H130 core and a
debond diameter of 200 mm.
All debonded panels failed by propagation of the debond to the edges of the panels. Figure 3.12
shows typical out-of-plane deflections of the debonded panels before and after debond
propagation measured by the DIC system. Prior to debond propagation, a large debond opening
can be seen corresponding to the buckling of the debonded face sheet.
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