DEVELOP CEMENTITIOUS MATERIALS INCOPORATING FLY ASH CENOPHERE FOR SPRAY-BASED 3D PRINTING

Developments of 3D printing in building and construction have attracted a lot of research focus during recent years. While the mainstream 3D printing of cementitious material adopts extrusion method, the limitation in vertical applications such as overhanging structures calls for further investigation of printing method with suitable materials. In this paper, spray-based 3D printing of cementitious material is proposed. The influence of incorporating fly ash cenosphere is studied for spray-based 3D printable cementitious material development. Rheological tests and robotic arm-controlled spray tests illustrate that the incorporation of fly ash cenosphere significantly reduces the spray splash, improves sprayed material distribution of sprayed material while impairs the pumpability of the material.