Structural forming of soil composites using as a pavement subgrade strengthening

• Published in: Case Studies in Construction Materials
• Main Authors: Pavel Pankov, Dmitry Bespolitov, Nikolay Shavanov, Nataliya Konovalova, Maria Ushkova, Aleksandr Karabtsov, Irina Tarasenko, Valery Petukhov, Igor Panarin, Mikhail Zayakhanov, Aleksandr Bituev
• Format: Article in Journal/Newspaper
• Language: English
• Published: Elsevier 2024
• Subjects: Composite materials; Organic-inorganic materials; Technogenic soil; Stabilizing additive; Structure formation; Cryogenic treatment; Materials of engineering and construction. Mechanics of materials; TA401-492; permafrost
• Online Access: https://doi.org/10.1016/j.cscm.2023.e02847; https://doaj.org/article/36e464a653434d21b66d9d3e3ce9ef34

The article substantiates the possibility of obtaining composite materials with improved functional properties to strengthen the subgrade, containing technogenic soil stabilized by an additive based on a gelling polymer. The introduction of technogenic soils into composites will not only reduce the consumption of expensive materials, but also solve a complex of acute environmental problems. Composite materials can be used in the construction of structural layers of road pavements, foundations of buildings and structures, sites for various purposes, for the prevention and elimination of defects in the foundations of engineering structures during their construction, reconstruction and repair, including in permafrost areas. Stabilized technogenic soils are more durable, frost-resistant and waterproof, which makes them applicable for creating impervious curtains in hydraulic structures and sealing storage facilities for hazardous substances. The cryogenic effect on a composite material allows one to vary its properties within a wide range and modify its macroporous structure. Studying the process of structure formation of the resulting organic-inorganic materials, consisting of macromolecules of high-molecular substances and inorganic inclusions that have undergone cryogenic treatment, will make it possible to specifically regulate their performance characteristics. The best values of strength characteristics were obtained for samples with a stabilizing additive concentration of 100 g/l. The resulting composite materials are hydrophobic, frost-resistant, characterized by a compressive strength of 2.3–6.5 MPa and a thermal conductivity of 0.19–0.20 W/(m·K). Data from differential scanning calorimetry and thermogravimetry and IR spectroscopy revealed that the binding of mineral particles by a stabilizing additive occurs due to the formation of organomineral complexes with the participation of clay minerals and the restructuring of hydration shells. SEM data indicate that crystallinity zones formed due to hydrogen ...