Performance test to evaluate the corrosion resistance of stainless steel in concrete

Abstract Stainless steel is a possible measure for increasing the service life of reinforced concrete structures exposed to chlorides. For the prediction of service life it is crucial to quantify the corrosion resistance of the material used by determining the chloride threshold at the steel concrete interface inducing corrosion at the rebar. However, currently the corrosion resistance of stainless steel is expressed by its pitting resistance equivalent number (PREN) which considers only the content of chromium, molybdenum and nickel along with certain factors. The higher the PREN-value, the more corrosion resistant the steel. But this PREN-value cannot be transferred into a chloride threshold concentration. Therefore, this paper presents a test method, the so called “ECISS”-test (ECISS = European Commission for International Steel Standardization), which enables the evaluation of the chloride threshold of stainless steel. The focus is on the performance of this test with respect to its limits and opportunities. Test results of different types of stainless steels are included and discussed. The benefit of stainless steel with respect to the service life of reinforced concrete structures is highlighted.