Soil-concrete for use in the 3D printers in the construction of buildings and structures

Abstract

Nowadays, the construction of cement composite using 3D printers is considered one of the most promising methods of automation of building processes. However, the compositions of cement composites have several disadvantages, such as high cost, short workability and etc. It has been suggested that clay soil as an additive will help to solve these problems partially. The aim of the work is development the cement compositions with clay soil, for use in 3D printers to construction. The composite consists of cement paste with clay soil and additives. To study printability of a composite the rheological properties in a fresh state were studied. The study of the rheological properties of composites was carried out using a flow table test for mortar. The key factor for determining the suitability of the composite for printing was accepted the diameter of the cone after shaking. The test results showed the possibility of replacing cement paste with clay soil up to 25% which leads to a reduction in the cost and an increase in printability with a slight decrease in the strength of the obtained material to 7%. Utilizing of soil from the construction site provides maximum economic efficiency of the material application.

Evaluating the Printability and Rheological and Mechanical Properties of 3D-Printed Earthen Mixes for Carbon-Neutral Buildings

“…The extrudability refers to its capability to produce continuous filaments of desired dimensions from the fresh plastic mix through the nozzle The extrudability of a printer refers to its capability to produce continuous filaments of desired dimensions from the fresh paste through the nozzle [22,59]. Extrudability evaluation was conducted manually via the 3D-printing of a single-layered filament with a width of 20 mm and a layer height of 10 mm in a square path with an area of 500 mm × 500 mm, as illustrated in Figures 4f and 6a.…”

“…The buildability test can evaluate how well a printed filament can support the deposited layers above it while retaining its dimensions [22,59]. A filament layer with a width of 20 mm and a height of 10 mm was considered to print the wall and cone geometries, as shown in Figure 6b.…”

“…Consequently, there is growing interest in using sustainable resources, emphasizing the importance of sustainable building materials. In the pursuit of sustainability, research into 3D printing with alternative construction materials like earthen materials, hemp hurds, and bio-based materials has garnered significant interest [22][23][24][25][26][27][28][29][30].…”

“…Previous publications have extensively explored soil printability and its applications in the construction industry from various perspectives [22,[43][44][45][46][47]. Barnes et al [43] evaluated different soil textures, including sand, silt, and clay, without additives regarding printability and water retention capacity.…”

“…In order to put into practice the plant-supported earthen building, researchers at the University of Virginia [45] printed a small wall prototype with the soil-seed combination that can sprout greenery. To overcome the high cost and improve the workability of cement composites for 3D printing, Iubin and Zakrevskaya [22] used clay soil as an additive to the 3D printable cement composite. They observed the positive impact of soil in increasing the workability time from 60-80 min to 160-200 min; however, adding clay soil decreased the compressive strength between 0.5-25%.…”