Figure 2 - available via license: Creative Commons Attribution 3.0 Unported
Content may be subject to copyright.
Source publication
The paper presents the results of the study of geopolymer composites reinforced with carbon and aramid fibers. Geopolymers were made on the basis of fly ash activated with 10 mole sodium hydroxide solution with an addition of aqueous sodium silicate solution. The fibers were introduced in the form of a roving. Carbon fibers 800 tex and aramid fiber...
Similar publications
Novel prefabricated insulating façade panels were developed from construction and demolition waste (CDW) aggregates under the framework of the European H2020 project InnoWEE. These non-structural components, aimed at improving the thermal efficiency of existing buildings, consist of an insulating plate covered by a facing layer made of CDW aggregat...
Mine tailings-based geopolymer was proved to be successfully created with enhanced strength for potentially construction and building materials applications. Through geopolymerization, the mining wastes can be reused and the storage, economic, and environmental issues can be mitigated. However, the geopolymerization effect was relatively limited co...
In the present study, the abrasive water jet machining (AWJM) of geopolymers prepared from fly ash, metakaolin and sand is discussed. The samples were prepared from sodium promoter, fly ash / metakaolin and sand. The process of activation was made using a 10M sodium hydroxide solution combined with a sodium silicate solution (the ratio of liquid gl...
This study aims to investigate the photocatalytic activity of ZnO nanoparticles as photocatalyst material which was doped onto a geopolymer paste. ZnO-doped geopolymer paste were prepared by mixing Class F fly ash and various amount of ZnO nanoparticles with alkali activator, which is combination of sodium hydroxide solution with sodium silicate. M...
Alkali-activated binders, more commonly referred to as “geopolymers”, have recently emerged as a good alternative to traditional binders (e.g., lime and cement) for soil stabilisation. Geopolymers utilise the alkaline activation of industrial waste to form cementitious products within treated soils, leading to enhanced soil properties. This paper a...
Citations
... The creation of a composite with improved fluidity and which could be applied in a thin layer could possibly be based on sodium silicates. An analysis of works [15][16][17]19,20] and other studies of alkaline binders suggested the possibility of creating an electrically conductive silicate composite based on water glass-sodium silicate for screen protection of structures that do not require restoration of the bearing capacity and repair of the surface. ...
This article presents the results of a study on the development of an anti-corrosion plaster composite based on water glass with increased electrical conductivity. Known acid-resistant quartz-fluorosilicate composites containing liquid sodium silicate, sodium fluorosilicate and acid-resistant high-silica filler in the form of quartz, andesite or diabase powder were chosen as the prototype. The low water resistance and low adhesion to Portland cement concrete of these composites limits their application. By adding granulated blast-furnace slag to the composite, it was possible to increase the water resistance of the solution and its adhesion to concrete. The addition of graphite filler to the composite made it possible to increase the electrical conductivity. This made it possible to obtain not only a corrosion-resistant (to chemical and physico-chemical corrosion) composite, but also to use it as a grounded protective screen to drain leakage currents from the structure, thus protecting it from both corrosion and electrocorrosion destruction.
... Furthermore, fiber-reinforced geopolymer is increasingly being studied to achieve better mechanical properties [6][7][8][9][10]. The enhancement of basalt, polyvinyl alcohol (PVA), polypropylene (PP), cotton, and carbon fibers exhibited significant improved mechanical performance of geopolymer composites at room temperature [11][12][13][14][15]. But, when exposed in high temperatures, the strengths of the fiber-reinforced geopolymer composites obviously decreased because of fiber degradation or melting, as well as matrix shrinkage and cracking [16,17]. ...
... This requirement often necessitates the use of fibers to improve composite properties [1]. Carbon, metallic, polymer, Kevlar, and E-glass fibers have been used as reinforcement materials in the production of fiber-reinforced composites for building construction applications around the globe [2][3][4]. Research findings have revealed that although these fibers significantly improve the mechanical properties of the composites, the high cost of the fibers limits their use in the production of composites [5]. Current materials and engineering research are increasingly showing concerns about developing energy-efficient and eco-friendly materials that will sustain the building industry [6][7][8][9]. ...
This study explored the use of coir fibers extracted from coconut husks, an agro-waste material that constitutes sanitation and environmental pollution problems, as a reinforcing element in the production of metakaolin-based geopolymer composites with improved properties. A series of sample formulations were produced with varying coir fiber content (0.5, 1.0, 1.5, and 2.0 percent weight of metakaolin powder). The investigation was conducted using a 10 M NaOH alkaline solution with a 0.24 NaOH:Na2SiO3 mass ratio. Samples were cured for 28 days and tested for bulk density, ultrasonic pulse velocity (UPV), and compressive and flexural strength. Microstructural examinations such as X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, and scanning electron microscopy (SEM) were also performed on samples. Compressive strength values up to 21.25 N/mm2 at 0.5% fiber content and flexural strength values up to 10.39 N/mm2 at 1% fiber content were achieved in this study. The results obtained showed a decreasing bulk density of geopolymer samples (2113 kg/m3 to 2045 kg/m3) with increasing coir fiber content. The geopolymer samples had UPV values varying from 2315 m/s to 2717 m/s. Coir fiber with 0.5–1.0% fiber content can be incorporated into metakaolin-based geopolymers to produce eco-friendly composite materials with improved mechanical properties for sustainable development.
... Research on the use of aramid fiber as a reinforcement in geopolymer material is a modification of the research carried out to date [59]. Aramid fiber has a number of characteristic properties that make it attractive for applications as reinforcements in geopolymeric materials. ...
... The motivation for undertaking research was the literature analysis in the field of 3D printing of fiber-reinforced Portland cement paste. The analysis showed the necessity of works in material strengthening and obtaining high bending and compressive strength properties, as well as changing the fracture from brittle to more ductile [39,59,[64][65][66]. Both metakaolin-and fly ash-based geopolymers were reinforced by long glass, carbon fiber, and aramid fibers. ...
The aim of the article is to analyze the structure and mechanical properties in terms of the cracking mechanics of geopolymer composites based on fly ash and river sand, as well as metakaolin and river sand with three types of reinforcement material: glass fiber, carbon fiber, and aramid fiber, in terms of their use in additive manufacturing. Geopolymer composites were reinforced with fibers in a volume ratio of 0.5%, 1.0%, and 2.0%. Subsequently, these samples were subjected to bending strength tests in accordance with the European standard EN 12390-3. The addition of fibers significantly improved the bending strength of all composites made of metakaolin and sand. The reinforcement with aramid fiber in the amount of 2.0% resulted in more than a 3-fold increase in strength compared to the reinforcement-free composites. An analysis of the morphology of the fibers was carried out on the basis of photos taken from an electron microscope. The correct addition of fibers changes the nature of the fracture from brittle to more ductile and reduces the number of cracks in the material.
... Alternative examples of fibers applied in geopolymers are synthetic fibers, such as aramid, polyacrylinite, polyamide, polyethylene, polypropylene, polyvinyl or polyvinyl chloride fibers [25,26]. Fly ash-based geopolymer composites reinforced with aramid fiber exhibited a rise in compressive strength by about 25% and a strengthen in flexural strength by almost 50% compared to unreinforced geopolymer composites [27]. Research on geopolymer composites with polyamide fibers was also performed. ...
This study investigated the influence of the steel and melamine fibers hybridization on the flexural and compressive strength of a fly ash-based geopolymer. The applied reinforcement reduced the geopolymer brittleness. Currently, there are several types of polymer fibers available on the market. However, the authors did not come across information on the use of melamine fibers in geopolymer composites. Two systems of reinforcement for the composites were investigated in this work. Reinforcement with a single type of fiber and a hybrid system, i.e., two types of fibers. Both systems strengthened the base material. The research results showed the addition of melamine fibers as well as steel fibers increased the compressive and flexural strength in comparison to the plain matrix. In the case of a hybrid system, the achieved results showed a synergistic effect of the introduced fibers, which provided better strength results in relation to composites reinforced with a single type of fiber in the same amount by weight.
... The research of geopolymer composites with aramid fiber was carried out using a geopolymer matrix based on fly ash and aramid fibers with a length of 30 mm and a diameter of 0.5 mm in an amount of 1.0% by volume [17]. The samples were cured at a high temperature: 85 • C for 10 h [17]. ...
... The research of geopolymer composites with aramid fiber was carried out using a geopolymer matrix based on fly ash and aramid fibers with a length of 30 mm and a diameter of 0.5 mm in an amount of 1.0% by volume [17]. The samples were cured at a high temperature: 85 • C for 10 h [17]. The results show increasing the mechanical properties-matrix material reached 70 MPa compressive strength, while composites with fiber addition reached 88.0 MPa [17]. ...
... The samples were cured at a high temperature: 85 • C for 10 h [17]. The results show increasing the mechanical properties-matrix material reached 70 MPa compressive strength, while composites with fiber addition reached 88.0 MPa [17]. A significant increase in value occurred also for flexural strength, respectively: 10.4 MPa for a composite with 1.0% fiber content, compared to the value of 7.1 MPa obtained for a matrix material and tensile strength-an increase from 3.1 MPa for matrix material up to 7.7 MPa for composite [17]. ...
The article describes the state of the art in reinforced geopolymers, taking into consideration various types of polymer fiber reinforcements, such as polypropylene, polyethylene, or polylactic acid. The description is focused on the usage of polymer short fibers and the mechanical properties of the geopolymer composites. However, to show a wider research background, numerous references are discussed concerning the selected studies on reinforcing geopolymer composites with long fibers and fabrics. The research method applied in the article is the critical analysis of literature sources, including a comparison of new material with other materials used in similar applications. The results of the research are discussed in a comparative context and the properties of the composites are juxtaposed with the properties of the standard materials used in the construction industry. Potential applications in the construction industry are presented. Moreover, the contemporary research challenges for geopolymer materials reinforced with fibers are presented.
In this article, various geopolymer applications in the context of both existing and potential future military applications are summarized. Geopolymers are a type of alkaline activated concrete binder with many advantageous properties over ordinary Portland cement based materials. Geopolymers are first compared to ordinary Portland cement based materials in regards to their mechanical properties, thermal properties, chemical resistance and CO2 emissions during manufacturing. History of geopolymer applications and research is also discussed. Then, various geopolymer applications are summarized, including their use as a passive fire protection, material for general construction, “ink”for 3D printing. These types of applications are also discussed in the context of existing and potential military applications of geopolymers, including their use by U.S. armed forces and U.S. military research. Superior geopolymer resistance to explosions is also presented.
A tremendous amount of the nonbiodegradable microplastic waste has been generated after the outbreak of COVID‐19 by the widespread use of single‐use personal protective equipment, especially disposable medical masks (DMMs). This has caused harm to the health and safety of human beings and various organisms. Finding a way to properly deal with these single‐use medical wastes has become an urgent problem. In this paper, an innovative way was explored to use DMMs in geopolymer (GP). The physical properties, mechanical strength, and resistance to high temperatures (200–800°C) of the composites were investigated. The findings of the study revealed that DMMs had negligible influence on resistance to high temperatures, but showed a positive influence on enhancing the compressive and flexural strengths of GPs at ambient temperature. The optimum DMMs content was 0.4 wt%, at which the compressive and flexural strengths of the GP composites were enhanced by 5.8% and 22.68% compared with the pure GP, respectively. The same polypropylene (PP) fiber amount increased compressive and flexural strengths by 7.49% and 9.76%, respectively. This thus confirmed that DMMs can be sustainably utilized in green building materials, playing a role as PP fibers toughening and contributing to the effective management of waste plastics.
This paper deals with investigation of changes in geopolymer wettability with increasing mass fraction of high-carbon fly ash and surface treatment by cold atmospheric plasma (CAP) to determine the influence of fly ash on wettability and whether it is a viable method to increase surface wettability for further surface treatment. In this study, multiple samples of geopolymers were prepared, including those with 16% and 32% of high-carbon fly ash from coal-fired power station. Wettability of samples was then measured before and after plasma treatment, both on surface and cut surface by using static sessile drop method to measure the differences in contact angle. While addition of fly ash only had low effect on the wettability, as in most cases, it only lowered the initial contact angle without speeding up the speed of soaking for compact geopolymer and actually slowed the soaking for foamed geopolymer, plasma treatment had significant impact and made the geopolymer completely hydrophobic, making plasma treatment a viable method to increase geopolymer wettability.
This paper deals with investigation of changes in geopolymer wettability with increasing mass fraction of high-carbon fly ash and surface treatment by cold atmospheric plasma (CAP). In this study, multiple samples of geopolymers were prepared, including those with 5% and 10% of high-carbon fly ash from coal-fired power station. Wettability of samples was then measured before and after plasma treatment, both on surface and cut surface. While addition of fly ash only had low effect on the wettability, as in most cases, it only lowered the initial contact angle without speeding up the speed of soaking for compact geopolymer and actually slowed the soaking for foamed geopolymer, plasma treatment had significant impact and made the geopolymer hydrophobic.
