Structural stability and design optimization of anisogrid conical lattice composite shells

Abstract

This paper presents a comprehensive investigation of the buckling behavior of isogrid conical lattice composite shells under axial compressive loads. This study focuses on the effects of critical structural parameters, including the outer shell thickness, rib thickness, rib angle, and number of ribs, on these shells' stress distribution and buckling behavior. A detailed parametric study was conducted using Finite Element Analysis (FEA) to model the mechanical response of the composite shells and assess the influence of these parameters. Furthermore, the Artificial Bee Colony (ABC) optimization algorithm was employed to determine the optimal set of parameters that enhance the buckling resistance of the structure while maintaining a low weight. The optimization approach aims to balance strength and efficiency, which are crucial for applications. Among the examined parameters, the outer shell thickness and rib angle were the most influential on structural stability. The results show that increasing the outer shell thickness improves the structural strength by up to 50 %, whereas decreasing the rib angle enhances the buckling resistance by 35 %. These findings highlight the importance of these parameters in the design of lightweight, high-strength composite lattice structures. This study contributes to the body of knowledge by offering an optimized design framework for conical lattice composite shells, providing valuable insights for the development of more efficient and stable structures for aerospace and other engineering applications. © 2025 Institution of Structural Engineers