New Printable Concrete Formulation Based on Fibers from Doum Palm Leaflets for 3D Printing of Energy-Efficient Buildings (2022-01)¶

Numerous countries throughout the world, including Morocco, are devoted to the process of sustainable construction in order to construct high-energy-efficiency structures capable of significantly reducing energy consumption during the various stages of construction. Among the innovative solutions for achieving sustainability in the field of construction is 3D printing technology, which allows for raw material savings, cost reductions on construction sites, and a significant reduction in CO2 emissions. The 3D printing of buildings, or additive manufacturing, is carried out by the injection of concrete, layer by layer, with a specific formulation and properties. This formulation could be developed by integrating ecological materials, which will contribute to the thermal inertia of buildings thanks to their low thermal conductivity. Several insulating materials have been proposed in this regard, including minerals such as natural basalt fiber, pozzolana, and hemp, and biological fibers such as flax, rapeseed, and palm leaflets. The objective of this article is to propose a new formulation of injectable concrete for buildings made by the 3D technique, which must be fluid to be used in the printer and firm to hold the times printed. This is done by using aggregates characterized by their low thermal conductivity and reinforcing fibers based on natural materials, providing thermal comfort to users. These fibers are, in particular, the leaflets of the doum palm, which are very abundant in Morocco and in the Mediterranean region, and their characteristics will be discussed in this article.