Enhancing the confinement of steel reinforced concrete using hexagonal auxetic structures

This study explores an innovative reinforcement approach for steel-reinforced concrete, utilizing auxetic steel structures with various hexagonal shapes to enhance confinement and mechanical performance. Finite element simulations reveal that the auxetic steel structure with the 3D plate model significantly improves ductility and provides robust confinement under compressive loads, outperforming the 3D stick model. In contrast, the 2D auxetic model achieves higher peak stress but exhibits greater brittleness. Furthermore, integrating auxetic and non-auxetic components in reinforced mortar, with auxetic parts in compressive regions and non-auxetic parts in tensile regions, significantly enhances flexural performance by increasing bending resistance and reducing crack propagation. By adjusting the re-entrant angles, these configurations can be optimized for improved mechanical properties. These findings underscore the potential of auxetic materials as valuable complements to traditional reinforcement methods, offering a novel pathway to improve concrete reinforcement strategies. © 2025 Elsevier Ltd