Free Vibration Analysis of Arbitrary-Shaped Plates Based on the Improved Rayleigh–Ritz Method

Table 14

Natural frequencies of the rectangular plate with circular opening in C-C-C-C boundary (Hz) (C-C-C-C).

Mode	Clamped
	Present	FEM	Error (%)
1	10.511	10.519	0.08
2	12.189	11.975	1.79
3	19.851	19.797	0.27
4	23.837	23.162	2.92
5	24.993	25.064	0.28
6	31.751	31.397	1.13