Effectiveness of Silicon Dioxide Nanoparticles (Nano SiO2) on the Internal Structures, Electrical Conductivity, and Elevated Temperature Behaviors of Geopolymer Concrete Composites

• Published in: Journal of inorganic and organometallic polymers and materials Vol. 33; no. 12; pp. 3894 - 3914
• Main Authors: Ahmed, Hemn Unis, Mohammed, Azad A., Mohammed, Ahmed Salih
• Format: Journal Article
• Language: English
• Published: New York Springer US 01.12.2023; Springer Nature B.V
• Subjects: Chemistry; Chemistry and Materials Science; Composite materials; Compressive strength; Construction materials; Electrical resistivity; Gels; Geopolymers; High temperature; Inorganic Chemistry; Multivariate analysis; Nanomaterials; Organic Chemistry; Polymer Sciences; Portland cements; Silicon dioxide; Splitting; Tensile strength; Thermodynamic properties; Thermogravimetric analysis; Mechanical properties; Elevated temperature; Electrical conductivity; Setting times; Geopolymer concrete; Microstructural analysis
• ISSN: 1574-1443; 1574-1451
• DOI: 10.1007/s10904-023-02672-2

The swift growth of urban areas and industries has resulted in a rise in concrete production and subsequent depletion of resources as well as environmental pollution. In light of environmental considerations, it has become imperative to discover and advance alternative binding construction materials that can substitute conventional Portland cement. Geopolymers have emerged as a viable solution to this issue. Geopolymer composites can benefit from unique attributes and improved performance through the use of nanomaterials. This is achieved by augmenting the composite’s microstructural features, creating additional C-S-H, N-A-S-H, and C-A-S-H gels, and filling in nanopores within the matrix. In this paper, extensive experimental laboratory works have been conducted to investigate the effects of adding different dosages (1, 2, 3, and 4%) of nano-silica (NS) particles on the setting times, compressive strength, splitting tensile strength, resistance to elevated temperatures, electrical resistivity, bulk electrical conductivity, thermogravimetric analysis and scanning electron microscopy of geopolymer concrete composites. As a result of the addition of NS, the mechanical strength, electrical conductivity, and thermal behavior of geopolymer concrete all improved by 21%, 36%, and 26%, respectively, in comparison to the control GPC mixture. Furthermore, according to SEM observations, the addition of NS improved the microstructural characteristics of the GPC specimens due to the formation of additional geopolymerization products. Finally, it was discovered through statistical and multivariate analysis that the developed model codes, such as ACI 318, ACI 363, AS3600, and CEB-FIP, are not suitable for predicting splitting tensile strength, electrical resistivity from their tested compressive strength values.