A Multimode Approach to Geometrically Nonlinear Free and Forced Vibrations of Multistepped Beams

Table 6

The first four eigenvalues for the three clamped-clamped beams (a, b, and c) where () = (1, 0; 0, 80; 0, 65; 0, 25) and (R₁; R₂; R₃; R₄) = (0, 25; 0, 30; 0, 25; 0, 20).

		Mode number
		1	2	3	4
Beam (a)	Present work	4.5405	7.6603	10.8088	14.0643
	[6]	4.5405	7.6603	10.8088	—
Beam (b)	Present work	3.5419	5.8116	8.4818	11.2834
	[14]	3.5419	5.8116	8.4818	11.2834
	[6]	3.5419	5.8116	8.4818	—
Beam (c)	Present work	3.3128	5.7316	8.5841	11.4491
	[6]	3.3128	5.7316	8.5841	—