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Aim of the research. The essence of the failure of the globally widespread theory of long-term resistance of reinforced concrete is defined and analyzed. Methods. This failure includes the following interconnected parts: 1) the set of ten basic fundamental properties of structural concrete is completely distorted (for example, instantaneous linear properties are Maxwell scheme); 2) mathematical rules are violated when recording the rates of elastic deformation and creep deformation, due to a misunderstanding of the Boltzmann principle (these violations distort the whole structure of the theory); 3) the rules of classical mechanics are violated, what is caused by substitution of fundamental properties of concrete with various “chain models” (for example, the principle of independence of action of forces, which is the fourth fundamental law of Galileo - Newton, is violated); 4) sections of the general “world theory of creep of reinforced concrete”, based on its algebraization, in their essence reject the fundamental law of natural science - Newton's second law: not only the inertial component is rejected, but also forces depending on speed (in this way the “world theory of creep of reinforced concrete” is degraded to the level of Aristotle’s mechanics); 5) unacceptably idealized creep theories and structural models that endow concrete with unrealizable properties, especially flagrant in zones of cracks, are incorporated in the normative calculations of structures; 6) solid design companies of the world show that concrete creep is not a scientific theory: this is a warning to designers. Results. The performed analysis is accompanied by necessary mathematical calculations and experimental estimates.

Concrete creep is of great practical importance and is taken into account in calculation and design of structures. The article discusses various options for describing the theory of creep of concrete, which are divided into three main groups: the theory of an elastic-creeping body (hereditary theory of aging), the theory of elastic heredity (the theory of an visco-elastic body), and the theory of aging. The main advantages and disadvantages of their use are demonstrated depending on various conditions and processes. Collisions in the study of concrete creep are clearly visible when considering expressions for the creep measure, as well as creep and relaxation nuclei. Different scientists propose their own modification of expressions that reflect various features of the material, and which are often very different from each other. The authors of the article obtained the full creep equations of structural materials.

Using the method of the planned experiment, mathematical models that establish a relationship between the technological parameters of the pyrolysis process of sludge-lignin with the characteristics of a porous surface of the synthesized active carbons are obtained. The nature of the influence of temperature and duration of the pyrolysis, the dosage of activating agent on the yield of carbon, the volume and specific surface of the pores are determined. The optimal conditions for obtaining adsorbents from sludge-lignin are established; the specific BET surface area was about 2000 m2/g.