Bistable characteristic of laminated shells with graded fibers

Based on an inextensional two-parameter analytical model for cylindrical shells, the relationships between the bistable properties of laminated shells with graded fibers and the distribution patterns of the fibers are studied in this article. The fibers are distributed through-thickness in power law from the middle surface to top or bottom surface. Two types of layup, i.e., antisymmetric and symmetric layups, are considered for obtaining the second stable configuration of laminated shells. The distribution regulation of the constituent volume fraction has been obtained for the availability of the second stable equilibrium configurations for both the symmetric and antisymmetric layups. It is showed that the laminated shells with symmetric layups are more difficult to form the second stable configurations than the shells with antisymmetric layups. The effects of the distribution patterns and Young’s modulus of fibers on the bistable configuration of laminated shells are examined. It is revealed that distributing fibers nearly to the top and bottom surfaces and higher Young’s modulus of the fibers are favorable to form second stable configuration and make it coil tighter.