About the Diagram Method of Determination of Parametric Points of Microcracking Formation Process in Concrete Elements under Axial Compression in Conditions of Low Negative Temperatures Action

Diagrams of axial, lateral and volumetric strains of concrete elements under axial compression in the conditions of low negative temperatures (in the frozen state) are built. It has been established that concrete samples in the frozen state have increased strength and increased limits of axial, lateral and volumetric strains under axial compression. The diagrams of lateral strains coefficient are built. The dependencies connecting the changes in the values of coefficient of lateral strains of the concrete with variable parameters of its stress-strain state under negative temperatures action are investigated. Based on the analysis of change patterns in lateral, axial and volumetric strains, patterns of microcracks forming in concrete elements in a frozen state are established. The influence of low negative temperatures on the change of parametric points (levels) of stress-strain state of concrete, characterizing the lower and upper boundaries of microcracks forming regions is established. The results of these investigations are used in development of the diagram method of reinforced concrete structures calculating at low temperatures action.

N.I. KARPENKO, Doctor of Sciences (Engineering), Professor, Academician of RAACS, (This email address is being protected from spambots. You need JavaScript enabled to view it.)
V.N. YARMAKOVSKY, Candidate of Sciences (Engineering), Honorary Member of RAACS, (This email address is being protected from spambots. You need JavaScript enabled to view it.)
S.N. KARPENKO, Doctor of Science, Counselor of RAACS
D.Z. KADIEV, Engineer

Research Institute of Building Physics of RAACS (21, Lokomotivniy Driveway, Moscow, 127238, Russian Federation)

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