Study of crushed stone-mastic asphalt concrete using fiber from fly ash of thermal power plants

Materials Science-Poland

Pershakov

et al. 2022

Self Cite

The introduction of new road-building materials with advanced physical and mechanical properties is the trend in contemporary civil engineering, which aims to increase the quality of road surfaces. The use of cast asphalt concrete in the upper layers of road surfaces as a replacement for layers made of traditional fine-grained asphalt concrete will not only increase the pace of construction and repair, but also the durability and quality of the road pavement. However, this method requires operational and economic optimization. Using fiber from the fly ash of thermal power plants is one of the solutions for the design of cast asphalt concrete compositions. The aim of the work is to design the optimal composition of hot cast asphalt concrete and cold cast emulsion–mineral mixtures with the use of fiber from the fly ash of thermal power plants for the construction of thin-layer coatings of highways of all categories and values; to study their properties; and to determine the feasibility of their use as reinforcing and stabilizing additives. The method of GOST 11506, namely, “Method for determining the softening temperature of the ring and ball”, with the apparatus “Lintel KiSh-20m-4” was used during the experiments. The use of standard laboratory tests made it possible to analyze the quality indicators of the materials under study and design the optimal compositions of hot cast asphalt concrete, taking into account the delamination of the mixture and the criterion of decomposition, in addition to exploring the properties of the obtained material.

Section: Resultsmentioning

confidence: 99%

Investigation of the properties of cast asphalt concrete mixture with the addition of fiber from the fly ash of thermal power plants

Materials Science-Poland

Pershakov

et al. 2022

Self Cite

“…Studies on the effect of additives that belong to the first category have shown that their introduction makes it possible to change the intensity of structure formation and dispersion of newly formed structures. When introducing such additives, it is necessary to remember that their acceleration, in some cases, can be less than expected under the additivity principle [34].…”

Section: Discussionmentioning

confidence: 99%

Development of building materials based on a high content of fly ash and polycondensation products from Chinese heat and power plants

Materials Science-Poland

Pershakov

et al. 2022

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The addition of fly ash from thermal power plants (TPP) and chemical additives, such as polycondensation products of acetone and formaldehyde, is an effective and economical method for increasing the strength and durability of building materials, in particular concrete. Fly ash added to the concrete and mortars at 10%–15% does not reduce their technical properties, while polycondensation products of acetone and formaldehyde plasticize and accelerate the hardening process of concrete. The study aims to substantiate the possibility of obtaining concrete on dense aggregates with a high content of fly ash through the use of polycondensation products of acetone and formaldehyde as additives, which are highly soluble in water and polyfunctional. The strength indicators were determined using standard methods. The study has shown quantitative changes in the properties of the fly ash-concrete mixture, improvement of its physical and technical characteristics, and durability of the fly ash concrete with the addition of polycondensation products of acetone and formaldehyde. In the present study, the authors determine the effect of fly ash addition on the properties of a concrete mixture, as well as the maximum possible content of fly ash that can be added to concrete to maximize certain properties required of the mixture; additionally, the same action is conducted with the addition of polycondensation products of acetone and formaldehyde concomitant with the addition of fly ash.

“…The resulting materials only consist of carbon, but they do not approach the extraordinary characteristics (for example, Young’s modulus) observed in single-walled carbon nanotubes obtained by laser ablation or electric arc synthesis. 45,46…”

Section: Discussionmentioning

confidence: 99%

“…The resulting materials only consist of carbon, but they do not approach the extraordinary characteristics (for example, Young's modulus) observed in single-walled carbon nanotubes obtained by laser ablation or electric arc synthesis. 45,46 Toxicity of nanotubes. Experimental results in recent years have shown that long multi-walled carbon nanotubes can elicit a response similar to that of asbestos fibers.…”

Section: Discussionmentioning

confidence: 99%

Technological aspects of the preparation of polymer composites of building materials and coatings

Polymers and Polymer Composites

TRACHEVSKYI

et al. 2022

Self Cite

In accordance with the principles of sustainable development, improving the quality and durability of structural elements and coatings, the construction industry requires the development and the implementation of resource- and energy-efficient building materials, as well as innovative technologies for their production. The use of complex modifiers for no-slump concrete mixtures and concrete is becoming increasingly widespread in modern materials science. The article presents the studies of influence of polymer additive structured carbon nanomaterials on physical and mechanical characteristics of no-slump concrete mixtures. The methods of infrared spectroscopy and thermogravimetric analysis showed that the use of carbon nanomaterials alters the structure of no-slump concrete mixtures significantly. As a result of the fact that the high-strength nanomaterial is the centre of crystallization of cement stone neo-formation, a denser reinforced microstructure is formed, which increases significantly the strength properties of no-slump concrete mixtures. The inclusion of a complex polymer additive in no-slump concrete mixtures leads to higher and longer plasticizing, which plays an important role in the production of monolithic products. It was determined that, in the presence of a complex modifier (a polymer additive structured by carbon nanotubes), the crystalline structure of calcium silicate hydrate is compacted, which determines high physical and mechanical characteristics of modified no-slump concrete mixtures. It was experimentally shown that the additive acted as an accelerator of a setting and hardening cement test and also increases its strength characteristics. In general, in this study, there is a water-reducing effect from the application of the additive for all no-slump concrete mixtures. Water consumption is reduced by 5% of the mass, while the strength is increased by 19%. No-slump concrete mixtures recipes modified by polymer additives, structured by carbon nanotubes, with high performance were developed.