Development of 3D printable construction materials

Today, the possibility of using 3D printing in the large-scale manufacturing processes of construction and architectural field are constantly explored. This is due to its advantages over traditional concrete manufacturing technology. Some of the advantages include reducing the labour force needed, a reduction in lead-time and flexibility in producing complex and non-standard shapes. For this report, the wet-mix spray process method for 3D printing is explored. The fresh and hardened properties of concrete are crucial to the success of the manufacturing process and therefore, rheological tests, tensile tests and compressive strength tests are carried out. The rheological properties of fresh concrete, namely yield stress and viscosity are assessed with regards to the effect of the addition of different materials to different mix deigns. Different ingredients have different effects on the rheological properties of fresh concrete, particularly for Fly Ash Cenosphere (FAC). FAC contributes largely to rheological properties of concrete, as compared to other materials. This report surveys the literatures of the effects of addition of different materials on the rheological properties of fresh concrete as well as the effect of curing on the tensile and compressive strength of hardened concrete. The methods to improve rheological properties of fresh concrete as well as tensile and compressive strength of the hardened concrete are discussed thereafter. In the last section, limitations and recommendations on 3D printing using wet-mix spray process are presented.Bachelor of Engineering (Civil