Accurate field potential measurements can detect corrosion. Corrosion of reinforcement steel in concrete is an electrochemical process. A potential field can be measured on the concrete surface by the use of an electrode, known as a half-cell, and a high-impedance voltmeter. The CANIN+ Corrosion Analyzing Instrument highlights corrosion activity before rust becomes visible. This early detection can be key in preventing an unanticipated structural failure.
 
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The instrument can measure the resistivity of the concrete. A lower concrete resistivity indicates a greater chance of corrosion of the reinforcement and also a greater corrosion rate. The resistivity of concrete can vary extensively depending on the local conditions and environmental influences. The combination of resistivity and potential measurement improves the information about the corrosion condition of the rebars.

The electrical resistivity method has been empirically proven to give an estimate of the corrosion rate.
 
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The permeability of concrete at the surface has been recognized as a major factor in determining the durability of concrete structures. The durability of a concrete structure relies on protective performance of a thin superficial layer of concrete, (cover concrete) “Covercrete”. This layer protects the reinforcement from corrosion caused by carbonation or the ingress of chlorides etc. Fast, reliable and non-destructive measurement of the permeability of concrete structures are able with Proceq’s Torrent.
 
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