Vibration Analysis of Plate with Irregular Cracks by Differential Quadrature Finite Element Method

Table 2

Natural frequencies of rectangular plates with several classical boundary conditions and irregular T-shaped, irregular L-shaped, and irregular I-shaped cracks.

Types	Mode numbers
	1	2	3	4	5	6	7	8	9
T-shaped; CCCC	4.2295	6.1142	6.9490	9.2834	10.5213	13.6350	17.1236	18.5392	19.1972
	4.2847	5.8950	6.7348	9.4992	10.5300	13.5580	17.2230	18.6560	19.2360
L-shaped; FCFC	0.4945	1.5181	2.2444	3.1847	3.5957	4.4550	5.2570	6.7095	7.6263
	0.4871	1.5894	2.2282	3.0957	3.5863	4.5244	5.1729	6.7097	7.5596
I-shaped; CFFF	0.2392	0.2519	1.3157	1.4969	1.7301	2.0860	3.6811	4.2399	5.1381
	0.2124	0.2889	1.3141	1.4914	1.7564	2.0674	3.6928	4.2317	5.1639

Results from ANSYS.