TO THE SAFE VALUE OF LONG-TERM LOADING OF COMPRESSED REINFORCED CONCRETE ELEMENTS
https://doi.org/10.33979/2073-7416-2023-106-2-80-89
Abstract
In the practice of calculations of compressed reinforced concrete elements for static effects, a number of questions important for determining the deformations and bearing capacity of these elements still do not have definitive and unambiguous answers. First of all, this is the problem of reliable accounting for the long-term effect of the external load. Unlike bending elements, the bearing capacity of compressed rods depends on the time they are under load.
The article deals with the influence of flexibility, the coefficient of reinforcement under long-term load on the decrease in the bearing capacity of a reinforced concrete compressed rod.
A calculation method is proposed to determine the long-term compressive force that provides a given period of safe operation of reinforced concrete columns.
The dependence of the ratio of the level of long-term action to the short-term breaking load on the deflections of compressed rods is revealed.
An analysis of experimental studies was carried out, indicating that the value of this ratio depends on the eccentricity of the longitudinal force, as well as data on the magnitude of the reduction in the long-term resistance of the columns.
Dependences of the stiffness ratio of the column under long-term and short-term external load on the flexibility of the rods, which is laid down in the current regulatory documents, and which is the determining factor in deciding whether to take into account the long-term nature of loading, are obtained.
This conclusion is confirmed by the data of the above experimental studies.
About the Author
Ashot G. Tamrazyan
National Research Moscow State University of Civil Engineering
Russian Federation
Russian Federation
doctor of technical sciences, professor, Corresponding Member RAAСS, head Department of Reinforced Concrete and Stone Structures
Moscow
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Review
For citations:
Tamrazyan A.G. TO THE SAFE VALUE OF LONG-TERM LOADING OF COMPRESSED REINFORCED CONCRETE ELEMENTS. Building and Reconstruction. 2023;(2):80-89. (In Russ.) https://doi.org/10.33979/2073-7416-2023-106-2-80-89
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