Calculation of reinforced concrete structures: considerations on developing new theory

Introduction. Current regulatory documents in the field of concrete and reinforced concrete are based mainly on research results obtained in the past century.

Aim. This article addresses the approaches to improve the theory of calculation of concrete and reinforced concrete structures, in the light of the accumulated knowledge.

Materials and methods. Since concrete structures belong to non-conservative systems, it is inaccurate to determine the forces arising in them using standard methods of structural mechanics. To achieve this goal, the deformation and relaxation problems for an axially compressed concrete fiber were solved following the A.A. Gvozdev and K.Z. Galustov’s two-component theory of creep, where deformations are categorized on the basis of reversibility.

Results. Historical background was provided. Proposed by the authors of this article is a solution to the deformation and relaxation problems for the elementary part of a concrete structure for the case of axial compression, since such an event is impossible. In this regard, it was suggested that estimating the loss of stability by Euler is also incorrect. It was observed that the achieved maximum load-bearing capacity of the construction is equivalent to zero resistibility, with a progressive collapse occurring. For further research, it was proposed to use the hypothesis of a straight normal, assuming that this law is valid in the absence of tangential stresses in the studied sections of the structure.

Conclusions. To improve the theory of calculation of concrete and reinforced concrete structures, it is necessary to revise drastically the existing approach to scientific research.

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