Mechanical performance of fractal-like cementitious lightweight cellular structures: Numerical investigations

Abstract Cellular structures with tunable mechanical properties are promising lightweight structures for prefabricated construction. In this study, a 3D fractal structure named Menger-Sponge (MS) cube is analysed. Besides, six other alternative fractal structures are designed with respect to different shapes of their associated hollow sections. Finite element method (FEM) is employed to predict the structure's mechanical behaviours under a uniaxial compression load. The numerical model is validated by experimental results obtained from author's previous publication. Comparisons are made between triply periodic minimal surface (TPMS-Primitive) and the second-order MS cementitious structure, and also among other fractal structures with different hierarchies. Results indicate that the MS and Primitive blocks have similar mechanical responses. The fractal-square (FS) structures exhibit better structural performances, especially for the first and second fractal orders. Overall, this numerical investigation shows the effect of the shaped holes and thinnest cross-section area on the hierarchically porous structure.