Analytical Dependences of the Effect of Material Density on the Strength and Deformability of Structural Concrete under Axial Compression

The study of the strength of materials and the use in further calculations of the main analytical dependencies obtained on the basis of ongoing experimental studies has always been an urgent and everyday task for scientists and engineers involved in the design of new material objects, including buildings and structures erected by builders. In the course of the work done, analytical dependences of the influence of material density on the strength and deformability of structural concrete under axial compression were derived, for this, the article considered the process of concrete destruction, analyzed existing views on the causes of destruction and hypotheses of the strength of bodies, modern building codes and rules. It was established that the modern approach to determining strength can no longer fully describe the process of material deformation, which establishes the relationship between stresses and relative deformations. Based on the results of the tests of prototypes of cubes 40х40х40 mm, 70х70х70 mm and prisms 40х40х160 mm, 70х70х280 mm from fine-grained slag concrete (FGSC), unified formulas were obtained for determining the compressive strength, the initial modulus of elasticity and limiting (maximum) relative deformations depending on the density of the material. Experimental and calculated strength and deformation characteristics of FGSC are given in the article. All this led to the conclusion that the main parameter that determines the strength is the initial modulus of elasticity of the material, in connection with this, the physical meaning of the modulus of elasticity was considered in more detail in the work.

N.N. CHERNOUSOV¹, Candidate of Sciences (Engineering) (This email address is being protected from spambots. You need JavaScript enabled to view it.);
B.A. BONDAREV², Doctor of Sciences (Engineering) (This email address is being protected from spambots. You need JavaScript enabled to view it.),
V.A. STUROVA², graduate student (This email address is being protected from spambots. You need JavaScript enabled to view it.),
A.B. BONDAREV², Candidate of Sciences (Engineering),
A.A. LIVENTSEVA², student

¹ OOO “NTO” EXPERT “ (office 314, 9, Kommunalnaya Square, Lipetsk, 398059, Russian Federation)
² Lipetsk State Technical University (30, Moskovskaya Street, Lipetsk, 398055, Russian Federation)

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