Free Vibration of Functionally Graded Sandwich Shallow Shells on Winkler and Pasternak Foundations with General Boundary Restraints

Figure 9

The difference of frequency parameters Ω obtained by CSST and FSDSST for simply supported FG spherical shallow shells with different thickness ratios h/a and anisotropic degrees E_m/E_c: (a) (1, 1); (b) (2, 1); (c) (1, 2); (d) (2, 2).

(a)

(b)

(c)

(d)