Dynamic Characters of Stiffened Composite Conoidal Shell Roofs with Cutouts: Design Aids and Selection Guidelines

Table 1

Fundamental frequencies (rad/sec) of clamped conoidal shell with central stiffeners.

Stiffener position	Stiffener along 𝑥-direction				Stiffener along 𝑦-direction				Stiffener along both 𝑥- and 𝑦-directions
	Nayak and Bandyopadhyay [13]	Present model			Nayak and Bandyopadhyay [13]	Present model			Nayak and Bandyopadhyay [13]	Present model
		8×8	10×10	12×12		8×8	10×10	12×12		8×8	10×10	12×12
Concentric	17.28	17.50	17.37	17.31	20.83	21.15	20.85	20.76	20.90	21.24	21.01	20.84
Eccentric at top	17.83	17.92	17.78	17.73	21.57	21.76	21.53	21.45	22.39	22.86	22.51	22.32
Eccentric at bottom	17.55	17.80	17.61	17.52	22.31	22.66	22.40	22.24	22.92	23.25	23.00	22.87

𝑎=50 m, 𝑏=50 m, ℎ=0.2 m, ℎ_ℎ = 10 m, ℎ_𝑙 = 2.5 m, 𝐸=25.4910×10⁹, 𝜈=0.15, 𝜌=2500 kg/m³, 𝑤_𝑠=0.3 m, and ℎ_𝑠=1 m.