Design Optimisation of Lower-Bound Buckling Capacities for FRP-Laminated Cylindrical Shells

Table 1

Reduced stiffness analysis results for each orthotropic shell.

Orthotropic laminate configuration	𝜎^∗𝑐𝑚(𝑖^∗𝑐𝑚,𝑗^∗𝑐𝑚)	𝑈2𝐵	𝑈^𝜃2𝐵	𝜕𝑉^𝑥2𝑀/𝜕𝜎^∗𝑐𝑚
	(×10^7Pa)	(×10^−5)	(×10^−5)	(×10^−12)(N/m^2)^−1
[0^∘]6	0.56 (8.3, 1)	2.139	2.030	−3.811
[90^∘]6	0.40 (6.3, 1)	2.256	2.195	−5.697
[0^∘,0^∘,90^∘]𝑠	0.47 (8.0, 1)	2.001	1.899	−4.234
[0^∘,90^∘,0^∘]𝑠	0.59 (7.6, 1)	2.354	2.262	−3.984
[90^∘,0^∘,0^∘]𝑠	0.78 (7.1, 1)	2.890	2.812	−3.690
[90^∘,0^∘,90^∘]𝑠	0.58 (6.8, 1)	2.515	2.443	−4.321
[90^∘,90^∘,0^∘]𝑠	0.66 (6.7, 1)	2.803	2.734	−4.243