Study of the Interaction of Cement-Based Materials for 3D Printing with Fly Ash and Superabsorbent Polymers

Abstract

The use of superabsorbent polymers (SAP) in construction is a relatively new trend, and not a completely explored area. However, SAP itself has been on the market for over 80 years. SAPs have a cross-linked three-dimensional structure, thanks to which they have the unique ability to absorb extreme amounts of water, up to a hundred times their weight. By using this property, it is possible to prevent water losses, which is important at the time of maturation in cementitious building materials. When there is a lack of water needed for hydration processes, the physical and mechanical properties deteriorate. The subject of this article is to determine the possible positive effect of the presence of SAP in the cement matrix in order to optimize the parameters of silicate composites for 3D printing. For this purpose, a special methodology was compiled consisting of tests through which it is possible to assess the suitability of the tested mixtures for 3D printing. This methodology consists of determining consistency, volumetric weight, ultrasonic analysis, buildability, X-ray diffraction, flexural tensile and compressive strength. For determining of buildability and ultrasonic analysis new methodologies were created in this research in order to be suitable for the 3D printing materials. Last but not least, efforts are also being made to increase the incorporation of secondary raw material (fly ash) in order to reduce the environmental impact of industrial production and, conversely, to increase its sustainability while maintaining or improving the mechanical–physical parameters of building materials. From the results presented in this paper it is apparent, that created methodology is efficient for determining properties of 3D printable mixtures. SAPs also significantly influenced properties of these mixtures. Mainly buildability and flexural tensile strength (by up to 30%) were increased and volumetric weight was decreased (by up to 5%).

Advancement in Sustainable 3D Concrete Printing: A Review on Materials, Challenges, and Current Progress in Australia

“…The most popular superplasticizers that have been used in the construction industry can be classified into four major types based on their chemical structure, as shown in Figure 6. Melichar et al [99] used a PCE superplasticizer together with defoaming admixture to decrease the water/cement ratio and increase the physical-mechanical properties of 3D printed cementitious materials. Polycarboxylate-based superplasticizer improved the flowability of the fresh concrete while achieving a water reduction rate greater than 30% [100].…”

“…Melichar et al [99] used a PCE superplasticizer together with defoaming admixture to decrease the water/cement ratio and increase the physical-mechanical properties of 3D printed cementitious materials. Polycarboxylate-based superplasticizer improved the flowability of the fresh concrete while achieving a water reduction rate greater than 30% [100].…”

Building a Greener Future: Advancing Concrete Production Sustainability and the Thermal Properties of 3D-Printed Mortars

“…FA, SF, and GGBS additions in concrete lead to early heat production due to a slower hydration reaction preventing thermal cracking, increasing resistance to a chemical attack, and improving mechanical performance, abrasion resistance, and long-term durability of the built structures [86][87][88][89][90]. Excellent environmental performances are achieved with a multi-component binder mixture with FA, SF, or/and GGBS or FA and SF in the formulation of printable mortars [47,91].…”

3D-Printable Concrete for Energy-Efficient Buildings

“…It can replace cement by 25-40% [28,29], but the setting time of concrete increases as the fly-ash content is increased [30]. There is an increased performance in buildability and smoothness in the end product as fly-ash content is increased up to 35% [31]. Table 3 shows the chemical composition of fly ash.…”

“…It can replace cement by 25-40% but the setting time of concrete increases as the fly-ash content is increased [30]. an increased performance in buildability and smoothness in the end product a content is increased up to 35% [31]. Table 3 shows the chemical composition of fl From Tables 2 and 3, it is seen that GGBS is a better fit for the partial replac cement than fly ash, based on its chemical composition.…”