Toughening by FragmentationÐ How Topology Helps*

In this brief overview, we present recent work on the novel concept of topological interlocking as a means of designing new materials and structures. Starting from a special self-supporting arrangement of tetrahedron-shaped elements that was discovered first, we proceed with the introduction of other shapes exhibiting topological interlocking. Unusual mechanical properties of assemblies of tetrahedrons that were studied both experimentally and theoretically are discussed. Possible applications can range from large scale mortar free construction in civil engineering to novel advanced materials based on microscale interlocking elements.