Petro Koval, Candidate of Technical Sciences (Ph.D.), Leading Researcher; Vladimir Zelenovskiy, Junior Researcher (State Enterprise «M. P. Shulgin State Road Research Institute»)
INFLUENCE OF CONCRETE COMPOSITION ON THE CORROSIVE STATE OF THE STEEL ARMATURES AND DURABILITY OF REINFORCED CONCRETE STRUCTURES
Abstract. The influence of the composition of the concrete mixture on the state of reinforcing steel as the main problem of corrosion of reinforced concrete structures is considered. The main attention is paid to the need for individual and mandatory consideration of the influence of the properties of additives to concrete on the passivation of reinforcing steel.
The purpose of conducting studies to determine the effect of concrete composition on the state of reinforcing steel is to analyze the causes of corrosion of reinforcement, determine the influence of the environment, apply appropriate prevention of this phenomenon and use methods to determine the corrosion state at the design stage of building structures for which reinforced concrete is used.
The composition of concrete, in addition to the standard set in various quantitative combinations (cement, gravel, sand, water) today it is advisable to use special additives.
Due to their correct and proportional application, you can create a mixture with significantly improved characteristics: with increased frost resistance, strength, durability, with accelerated or delayed setting of the mixture, etc. Nevertheless, you should not forget that the individuality of the composition of additives could affect the ability of concrete to passivate reinforcing steel.
It is possible to eliminate the possibility of reducing the passivation of concrete by testing reinforced concrete samples for its protective properties in relation to the reinforcement.
The test method is based on the passivation of reinforcing steel in an alkaline environment and consists in evaluating the protective effect of a sample of concrete in relation to a sample of steel reinforcement by comparing data obtained with a change in potential depending on changes in the density of electric current passing through the sample.
The issue of quality and durability of reinforced concrete structures, both technically and economically, is attracting increasing attention of builders. It is obvious that in most cases an increase in the initial cost of manufacturing the structure and its reliable protection is economically justified, if this allows reducing the number and cost of repairs during operation.
Keywords: reinforcement, corrosion, concrete, reinforced concrete, concrete additive, concrete composition, corrosion state of reinforcement, durability of reinforced concrete structures.
1. Alexev, S. N. (1967). Korroziya i zashchita armatury v betone. [Corrosion and protection of reinforcement in concrete]. Moscow.
2. Baikov, V.N., Sigalov, E.E. (1984) Zhelezobetonnyye konstruktsii. Obshchiy kurs. [Reinforced concrete structures. Overall course]. Moscow.
3. Dubіnchik, O. I. (2005). Vplyv koroziyi betonu ta armatury na dovhovichnistʹ zalizobetonnykh prohonovykh budov mostiv. [Injection of corrosion concrete and reinforcement for the passage of concrete passage walkways of bridges]. Bulletin of Dnipropetrovsk National University of Social and Transport Transport. Journal “Science and Progress Transport”. Dnipropetrovsk. DOI: https://doi.org/10.15802/stp2017/115385
4. Puzanov, A.V. (2010). Metody obsledovaniya korrozionnogo sostoyaniya armatury ZHBK [Methods for examining the corrosion state of reinforced concrete structures]. St. Petersburg.
5. Korifeld, N. A., Prytula, V. L. (1969). Zakhyst zalizobetonnykh konstruktsiyi vid koroziyi, shcho vyklykayetʹsya blukayuchymy strumamy [Protection of reinforced concrete structures from corrosion caused by wandering currents]. Concrete and Ferro-concrete Journal. Poltava.
6. Demin, Y. V., Demina, R. Y. (1998). Obespecheniye dolgovechnosti elektrosetevykh materialov i konstruktsiy v agressivnykh sredakh [Ensuring the durability of power grid materials and structures in aggressive environments]. Novosebirsk.
7. Corrosion of concrete. All about corrosion. Retrieved from http: //www.okorrozii.com.html
8. Building materials and technologies. Retrieved from http://www.bronepol.ru
9. SE SRIBC. (2010). Structures of buildings and structures. Protection of concrete and reinforced concrete structures from corrosion. General technical requirements: DSTU B V.2.6-145:2010. State Standard of Ukraine.
10. SE SRIBC. (2012). Protection of concrete and reinforced concrete structures from corrosion. Test methods: DSTU B V.2.6-181:2011. National Standard of Ukraine.
11. Council for Mutual Economic Standard. (1983). Assistance The protective properties of concrete in relation to steel reinforcement. Electrochemical test method. Council for Mutual Economic Assistance Standard: ST SEV 4421-83.
12. SE SRIBC. (2009). Additives for concrete and mortar. General technical conditions: DSTU B V.2.7-171:2008. National Standard of Ukraine.