EXPERIMENTAL INVESTIGATIONS OF REINFORCED CONCRETE BEAMS OF CIVIL BUILDING EXTERNAL WALLS

The relevant building codes don't contain methods of calculation of remaining life of reinforced concrete structures. The explanation is that developed methods don't allow to consider many factors concerned with durable exploitation of structural elements:changing loads occurs both in amount and mode and direction of the influence, technological impacts not foreseen by the project are possible, corrosive damages occur and accumulate, the initial deformation-strength properties of concrete and reinforcement are changed. To solve this problem it's important to test the structures, that suffered from real environment conditions.Development, approbation and inclusion of complex engineering methods of forecasting and methods of estimation of the residual life of reinforced concrete structures in normative documents is an actual scientific task facing the researchers in the field of construction.The creation of a modern practical methodology will increase constructive safety in the long-term operation of infrastructure facilities, and will provide an opportunity to more effective manage capital investments in the real estate market.The results of the experimental investigations of reinforced concrete beams of civil building external walls are given in the article. The deformation mode of the specimens until their rupture is described. Manufactuiring defects, exploitation corrosion damages and their influence on stress-strain condition of structures are presented. It is noted that in the manufacture of reinforced concrete structures it is necessary to increase the level of quality control of the manufacture of reinforcing frames and to ensure their project position when concreting.

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