Keywords: asphalt concrete

INVESTIGATION OF THE PROPERTIES OF ASPHALT CONCRETE ON MODIFIED BITUMEN POLYMERS

https://doi.org/10.58224/2618-7183-2022-5-4-19-29
Abstract
The paper considers the method of obtaining bitumen modified with a Honeywell TitanTM7686 polymer additive and the preparation of asphalt concrete mixtures based on it. The aim of the work is to study the properties of the obtained bitumen and the possibility of its use in road organizations of the Vladimir region for the manufacture of asphalt concrete with improved deformative indicators. The study was carried out on bitumen BND 70/100 LLC LUKOIL – Nizhegorodnefteorgsintez, determined not only the main indicators of bitumen, but also some additional ones necessary to determine the intervals of mixing and compaction. A step-by-step algorithm for introducing an additive into bitumen is described, the optimal amount of the introduced modifier, temperature and mixing time are determined. The obtained test results of the modified bitumen were compared with the data of the initial samples. Next, the selection of the composition of the asphalt concrete mix was carried out and samples were made on modified bitumen and bitumen without a modifier. From the prepared asphalt concrete mixture A16Vn on bitumen modified by Honeywell Titan 7686, the top layer of the coating with a thickness of 4 cm was laid on the pilot site. After the installation of the asphalt concrete layer, cuttings were selected and studies of the selected samples from the coating were carried out. The test results showed a significant improvement in the main indicators of asphalt concrete mixtures and asphalt concrete, as well as resistance to rutting, which could not be achieved without the use of a modified binder.
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DESIGNING THE COMPOSITION OF ASPHALT CONCRETE BY THE CALCULATION METHOD

https://doi.org/10.58224/2618-7183-2022-5-3-5-16
Abstract
The article proposes a promising technology for designing asphalt mixes based on the method of "irregular packing" of figures of different sizes and shapes. The calculation has been improved and adapted to deter-mine the bulk density of asphalt concrete depending on the content of bituminous binder. A detailed algorithm for designing asphalt mixes based on the "irregular packing" method is described. MS Excel spreadsheets have been created with calculation formulas for converting the grain composition of the mineral part of the asphalt concrete mixture, the content of bituminous binder by volume and recalculating the bulk density of asphalt concrete, the content of air voids, voids in the mineral aggregate and voids filled with bituminous binder. In order to justify the application of the "irregular packing" method of figures of different sizes and shapes in determining the bulk density of asphalt concrete, the results of the calculated data were compared with laboratory tests of control samples during the preparation of ShMA-16 and A 16Vn asphalt concrete mixes at the plant, as well as cores taken from the coating on highway. As a result of the comparison, it was found that the discrepancy between the obtained experimental and calculated values in terms of bulk density does not exceed 0.02 g/cm3, and in terms of the content of bituminous binder, less than 0.2%.
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INCREASING THE EFFICIENCY OF MINERAL POWDER FROM TECHNOGENIC RAW MATERIALS DUE TO ITS HYDROPHOBIZATION

https://doi.org/10.34031/2618-7183-2020-3-4-24-30
Abstract
Abstract: a promising direction in solving the problem of obtaining high-quality asphalt concrete is the use of mineral fillers, including from industrial waste.
The article considers the use of OEMK slag as a mineral powder in the asphalt concrete mix.
The influence of hydrophobization of mineral powder by GF Preparation on moisture absorption and its structuring ability to change the maximum shear stress from the content of mineral powder before and after hydrophobization was studied. It is established that the treatment of the filler provides the necessary hydrophobicity of the mineral material, reduces the bituminous capacity, water saturation, porosity of the asphalt binder, and increases its strength and water resistance. The results of studies of the main characteristics of asphalt concrete on the example of a mixture of type G III of the brand showed that as a result of hydrophobization, the strength, water resistance, water saturation, and swelling of the composite significantly increase.
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DIRECTED REGULATION OF PROPERTIES OF ASPHALT CONCRETE BY NANOCARBON OBJECTS

https://doi.org/10.34031/2618-7183-2019-2-3-65-71
Abstract
Directed regulation of asphalt concrete properties is an important condition for obtaining a durable material that minimizes operating costs. One of such perspective directions is modification of building compositions by nanoscale objects. The method of modification of mineral powder from dolomite by carbon nanotubes is considered in the work, and results of tests of asphalt concrete on its basis are given. It is shown that the use of nanomodified dispersed dolomite in the technology of preparation of asphalt concrete mixture on the surface of the grains of mineral material forms a strong, high-temperature resistant layer of structured bitumen. The increase in the dynamic viscosity of bitumen and the complex shear modulus under the influence of CNT contributes to the change in the yield strength of asphalt concrete above the maximum shear stresses, which leads to a slight accumulation of residual plastic deformations in the plate in the study of the resistance to ruts. Thus, modification of bitumen and asphalt concrete with nanoscale additives can be an effective tool in the fight against plastic deformations such as shifts, surges and rutting in hot climates, for example, in Jordan.
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ANALYSIS OF THE INFLUENCE OF THE QUALITATIVE COMPOSITION OF THE ASPHALT-CONCRETE MIXTURE ON THE MAIN PERFORMANCE CHARACTERISTICS OF ASPHALTIC CONCRETE PAVEMENT

https://doi.org/10.34031/2618-7183-2019-2-1-17-23
Abstract
The paper presents an analysis of information quality assurance of production of asphalt concrete mixtures, as well as the study of the relationship of the qualitative composition of asphalt concrete mixtures and physical and mechanical characteristics of asphalt concrete pavement. The study of the main characteristics was carried out on the example of asphalt concrete type B and grade I and crushed-mastic asphalt concrete – SchMA-20. It is established that the deviation of asphalt mixtures in composition from the required values leads to their under-compaction in the pavement. It is also established that increasing the number of inconsistencies in the asphalt concrete mixture leads to an increase of physical-mechanical characteristics that differ from the requirements of GOST 9128-2013 and GOST 31015-2002 respectively. As an information base for the assessment of the influence of granulometry of the mineral part of asphalt concrete, as well as the amount of bitumen on the main characteristics of asphalt concrete, the data of the current ACP of Belgorod region were used. Analysis of the particle size distribution was carried out using a laser analyzer of asphalt ABA7/35B. The obtained data became the basis for a further study of the influence of various parameters on the properties of asphalt mixes, as well as improving the efficiency of the asphalt mix production management system.
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