Review on 3D printed concrete as structural beam members

Recently, Three-Dimensional Concrete Printing (3DCP) has gained its popularity as
construction material. It offers several advantages over conventionally casted concrete such as
absence of formwork, reduction of construction equipment transportation, greater safety,
reduction of labour cost, and many others. However, the technology also comes with many
challenges. Researches in this area can be classified into two issues which are fresh and hardened
states of the printed concrete. Investigation of fresh concrete focuses on the optimal design of
rheological properties which determines the pumpability, extrudability, and buildability. While
mechanical properties of hardened 3DCP are usually investigated by adopting standard tests for
conventionally casted concrete. However, due to the complexity of printing process, it is often
that 3DCP behaviours cannot be predicted by its mechanical properties obtained from the tests.
This paper reviews some studies done by others to highlight potential manufacturing process
related weak points of 3DCP as structural beam members.