Modelling of 3D concrete printing process: A perspective on material and structural simulations

3D concrete printing (3DCP) offers solutions for affordable construction including cost minimisation, produc-tivity improvement, and sustainability alignment, as well as being able to tailor products with complex design requirements. Various 3DCP techniques, printable materials, and computational design tools have been devel-oped to meet the requirements of mechanical and structural properties as well as durability. Coupled with parametric design and numerical simulation approach, the 3DCP could enable further construction optimisation, and realisation of complex designs. While major effort is devoted to developing materials and mix designs, limited attention is given to the development of predictive modelling and design optimisation specifically for 3D printing of concrete/mortar from the fresh to the hardening states. The benefit of additive manufacturing in construction is often recognised by the building of highly complex structures obtained from the generative design or structural optimisation processes. Here, various constraints need to be considered, such as overhang angle, printing direction, anisotropic properties of concrete, and printing toolpath optimisation. Continuous improve-ment in non-deterministic/statistical or machine learning (ML) approach could also lead to the development of a future robust 3DCP simulation tool when data is scarce or limited. This work will provide a snapshot of the current state-of-the-art development of modelling and design optimisation tools for 3D concrete printing.