Influence of the 3D material tailoring on snap-through and snap-back post-buckling behaviors of steel-wire-reinforced hybrid 3D graded orthotropic shallow cylindrical panels

Simultaneous application of composite layers and steel bars/wires may considerably increase buckling strength of the civil structures. In the present paper, influence of the material heterogeneity on snap-through and snap-back post-buckling behaviors of the steel-wire-reinforced hybrid functionally graded orthotropic shallow cylindrical panels is investigated. In this regard, various arrangements are adopted for the steel-wires to constitute 3D (simultaneous radial, circumferential, and axial) gradations of the materials within some layers in addition to using some traditional composite layers in between. The non-linear governing equations of post-buckling are derived based on the principle of minimum potential energy. Sanders' shell theory is utilized to ensure that the results are reliable in the deep post-buckling region. A nonlinear finite element scheme is employed to trace the post-buckling paths using the modified arc-length method. Finally, some parametric studies in terms of material arrangement, size of the embedded steel wires, the overall lamination scheme, and geometric parameters of the shell are performed. Results emphasize the significant effects of the steel wires on the post-buckling strength and indicate the advantage of using steel fibers with exponential or uniform longitudinal distributions and linear transverse distribution, for weight optimization.