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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.

Wood as a structural material differs from other materials used in construction and industry, high variability of its properties. This is due, among other things, to the action of various variable factors – moisture content, temperature, inclination of fibers and others. The influence of wood moisture is especially strong – as a result of moistening the strength of wood considerably decreases in comparison with durability in absolutely dry condition. In addition, wood is a significantly nonlinear structural material. Non-linearity is manifested both in short-term and prolonged loading. Research of wood in time can be divided into two directions: longterm durability of wood and creep of wood. Modern models of wood creep are based on linear theories. Analysis of experimental data of various researchers on wood creep, has shown that the area of linear creep is observed at rather low levels of loading. At medium and high levels of experimental loading the existing models of linear wood creep theory do not correspond to experimental data. All this points to the actuality of the development of methods of calculating wooden structures for creep (linear and nonlinear), taking into account the wood moisture.

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This article identifies and investigates the errors in the foundations of the modern theory of creep of reinforced concrete caused by the use of the principle of superposition, which is an extensive interpretation of the principle (scheme) of the linear superposition of Boltzmann. The results of the analysis published by the authors in the journal of Structural Mechanics of Engineering Constructions and Buildings No. 6 of 2017 and No. 3 of 2016 are supplemented. The article was written in accordance with the recommendations of the round table held in the RUDN University on June 9, 2016, under the guidance of D.Sc., prof. Krivoshapko S.N.