Damage Detection in Plates with the Use of Laser-Measured Mode Shapes

Table 3

Organization of measurements during practical experiment along with the first five natural frequencies of the plate.

Measurement no	Specimen state	F1	F2	F3	F4	F5
M#1–M#4	Intact, T = 20 C, reassembly	16.59	90.38	236.08	420.14	475.25
M#5	Intact, T = 34 C	16.62	90.24	235.53	418.07	474.29
M#6	Intact, T = 36 C	16.56	90.16	235.26	421.77	473.89
M#7	Intact, T = 30 C	16.59	90.50	236.45	419.16	475.50
M#8	Intact, T = 20 C, reassembly	16.64	90.59	236.68	419.65	475.74
M#9	Damage 1, 5 mm	16.65	90.58	236.63	417.83	475.50
M#10	Damage 1, 7.5 mm	16.65	90.49	236.39	418.49	475.07
M#11-M#12	Damage 1, 10 mm, reassembly	16.67	90.49	236.23	418.80	474.77
M#14	Damage 2, 5 mm	16.66	90.50	236.32	417.47	474.23
M#15	Damage 2, 7.5 mm	16.63	90.46	236.41	411.91	474.04
M#16–M#20	Damage 2, 10 mm, reassembly	16.63	90.49	236.44	413.59	474.08
M#21	Damage 3, 10 mm (1/4 cut)	16.82	89.40	231.47	385.26	450.84
M#22	Damage 3, 20 mm (1/2 cut)	16.69	89.15	229.78	384.73	447.43
M#23	Damage 3, 30 mm (3/4 cut)	16.24	65.26	87.69	200.32	226.14
M#24–M#26	Damage 3, 40 mm (full cut), reassembly	16.25	65.26	87.75	200.24	226.34