Case Studies in Construction Materials (Dec 2023)
Road soil concrete based on stone grinder waste and wood waste modified with environmentally safe stabilizing additive
Abstract
In this paper, the possibility of recycling large-tonnage wastes of stone crushing and wood wastes in the compositions of road soil concretes is substantiated. The developed road construction materials can be used for the construction of structural layers of pavements, bases, foundations, sites for various purposes, which will reduce the consumption of expensive traditional materials and solve a set of acute environmental problems. The article presents data on the chemical and phase composition, properties and features of the structure of waste, obtained using modern physical and chemical research methods. The effectiveness of the complex use of a mineral binder and a stabilizing additive of a polymeric nature in the production of soil concrete is shown. The optimal amount of raw materials has been established, which makes it possible to obtain frost-resistant soil concrete with a strength grade of M60–M75. Using the methods of scanning electron microscopy, X-ray diffraction analysis, differential scanning calorimetry and thermogravimetry, infrared spectroscopy, the features of the structure of soil concretes were studied. It is shown that the structure formation of stabilized samples is accompanied by dehydration, carbonization and an increase in the connectivity of orthosilicate anions. Aggregation of dispersed particles of raw materials contributes to the appearance of neoplasms with a dense microstructure. It has been experimentally confirmed that the stabilizing additive interacts with all raw materials and contributes to their structural changes. It was revealed that the polymer component of the additive is involved in the complex formation by the donor-acceptor mechanism with aluminates and aluminoferrites, which are part of the mineral binder; promotes demethylation of the structure of hydrolytic lignin; leads to hydration and an increase in the connectivity of orthosilicate anions when interacting with minerals of rock crushing waste. Biotesting with test objects Daphnia magna Straus and Chlorella vulgaris Beijer proved that the developed stabilizing additive does not have an acute toxic effect on test objects and is safe for the environment.
