Influence of Armature Corrosion Products on Its Ferromagnetic Properties

ABSTRACT

The material of the article contains results of pilot research of the influence of product structure of corrosion of steel armature and chemical structure on instrument readings to determine degree of a corrosion condition by a nondestructive method. As we know corrosion of reinforcement leads to the loss of bearing capacity of the construction and its subsequent destruction, in this regard, the relevant definition of corrosion condition of maintained buildings rebar is essential. The basis of this method of nondestructive corrosion monitoring of rebars in reinforced concrete products and structures is connected with the fact that in a certain region of frequencies generated by the ferromagnetic properties of the steel and its corrosion products are different. The purpose of the research was detection of dependences when using the device based on frequency a differential and ferromagnetic evaluation method of armature corrosion condition. It was obtained data according to the influence of such corrosion products like FeO, Fe (OH)₂ and Fe₂O₃ on the readings in the laboratory. The results obtained allowed to identify the greatest impact of one of the corrosion products such as Fe(OH)₂ on the device. There was also experimentally considered the influence of a penetration depth of ferromagnetic corrosion products to a protective layer of concrete on instrument readings. So, with the increase in a penetration depth of ferromagnetic corrosion products in a protective layer of concrete on 10 mm, which is equivalent, in first approximation, penetration of ferromagnetic corrosion products in this distance, instrument readings increase for 15–18 %. These experiments confirm prospects of using of the device for determination of the corrosion condition of armature based on frequency differential and ferromagnetic evaluation method.

Keywords: reinforcement corrosion, instrument, nondestructive method, the thickness of the protective layer, ferromagnetic properties.

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ISSN 2076-6033