Bioinspired cellular cementitious structures for prefabricated construction: Hybrid design & performance evaluations

Abstract

Lightweight cellular structures with porous architectures and controllable mechanical characteristics are promising candidates for a broad range of prefabricated engineering applications. A triply periodic minimal surface (TPMS) structure that is a naturally inspired continuous non-self-intersecting surface is a bioinspired cellular structure. In this work, we investigate a novel approach based on a combination of primitive-TPMS cells and cubic blocks along with lattice and gyroid-TPMS cells achieving 50% volume fraction cellular structures. Lightweight cellular specimens made of cement mortar with 3D printed sacrificial thermoplastic Polylactic Acid (PLA) moulds are subjected to uniaxial compressive loadings. Compression tests are carried out on the cement cubes, while tensile behaviours follow the simplified damage plasticity model, which is used to obtain the material properties for the input model data. Finite element (FE) analysis is employed to predict mechanical performances such as stress distributions, stress-strain curves, and the damage mechanisms of three representative cellular structures (primitive, lattice, and gyroid). Compressive experiment tests are conducted on these blocks and validated by the FE model. Results indicate that the mechanical responses of the cellular structure, wherein primitive cellular structures yield the highest compressive strength, could be predicted accurately through the FE analysis, and outcomes from both numerical models and experimental tests are validated.