Impact performance of topologically interlocked concrete tubes: linking geometric design to mechanical response

• Impact performance of topological interlocking concrete tubes is evaluated. • The influence of key geometric parameters is systematically assessed. • Full-sine interfaces limit sliding, while half-sine profiles allow more flexibility. • Hexagonal patterns enhance stress redistribution; squares localise force transfer. Topological interlocking is an innovative structural strategy that enhances mechanical performance by connecting discrete elements through interlocking geometries, eliminating the need for connectors. While previous research has predominantly focused on the quasi-static behaviour of interlocking structures, their dynamic performance, particularly in topologically interlocked tubular assemblies, remains insufficiently understood. Moreover, the influence of key geometric parameters such as polygonal base pattern, interface curvature, and segmentation on impact resistance have not been examined. This study develops a series of non-planar topological interlocking bricks featuring controlled interface curvature and diverse polygonal patterns for the construction of tubular assemblies. A validated finite element model is employed to conduct parametric analyses, assessing the influence of polygonal configuration, interface curvature, and segmentation level on structural flexibility, peak contact force, damage distribution, and energy absorption under impact loading. The findings shed light on the influence of interlocking geometry on structural dynamic behaviour and provide a foundation for the rational design and optimisation of topologically interlocked tubular assemblies in impact-resilient applications.