Effects of Delamination on Guided Waves in a Symmetric Laminated Composite Beam

Table 4

Natural frequencies (Hz) obtained by SEM for the delaminated composite beam shown in Figure 5 (𝑙_𝑤 = 5 mm, 𝑟=0.25).

Mode	Delamination length (mm)
	0	5	50	100
1	3.9496	3.9483	3.9366	3.9230
3	69.244	69.244	69.198	68.887
5	223.90	223.90	223.42	220.29
10	989.25	987.91	977.62	962.29