Global buckling and multiscale responses of fiber-reinforced composite cylindrical shells with trapezoidal corrugated cores

In order to comprehensively understand the effect of composite materials on the structural response, a novel multiscale numerical model is presented in this work to study the global buckling and localized responses of composite cylindrical shells with trapezoidal corrugated cores. Treated as hierarchical structures, the investigation of composite shells includes carbon fiber-reinforced composites at micro-scale, fiber-matrix laminates at meso-scale, as well as corrugated shells at macro-scale. The well-established locally-exact homogenization theory is firstly introduced to generate the microstructural effective coefficients, which are then transferred to the lamination theory. Finally, a simplified structural homogeneous representative volume element (RVE) is established with equivalent properties to a part of cylindrical structures with inner and outer skins embedded with corrugated cores, significantly facilitating the finite element (FE) simulations. The simplified structure is validated against the 3D full-scale analysis with good agreement for critical loads of different buckling modes. The global buckling performance of corrugated cylinders is then demonstrated by considering the effect of constituent materials, fiber volume fraction and geometric parameters. More importantly, benefited from a top down procedure, the localized stress distributions are recovered using the three-stage multiscale model, to predict the possible crack initiations starting within the microstructures.

Automated summary

A novel multiscale numerical model is proposed in this study to investigate the global buckling and localized responses of composite cylindrical shells. By introducing a top down procedure from micro to macro scales, a simplified structural model is established to facilitate the finite element simulations.