APPLICATION OF MARINE CLAY CONCRETE FOR 3D CONCRETE PRINTING OF A TRUSS STRUCTURE

Abstract

Particularly in developed economies, the construction sector has contributed significantly to carbon emissions. Utilizing and recycling construction waste in a city like Singapore thus becomes a relevant consideration for sustainability, as doing so can result in an immense reduction of carbon footprint. As a high proportion of construction waste in Singapore comprises of marine clay, the feasibility of employing waste marine clay in construction is explored. The thesis administers the technique of 3D concrete printing to utilize the waste clay, potentially allowing greater precision, shorter time, lower cost and improved efficiency in the construction process. In the trial, a 1.8m truss structure was designed and 3D printed. The rheological properties of the trial mix, which was concrete incorporating uncalcined marine clay as an additive, was assessed. It was found that the presence of marine clay in the test mix increased the static yield stress due to the increased water demand, consequently lowering the workability of the test mix. The test mix was evaluated to be viable and met the strength requirements.