Improving durability of reinforced concrete structures using migrating corrosion inhibitors

Author(s): B. Bavarian and L. Reiner
Paper category: Workshop
Book title: RILEM International workshop on performance-based specification and control of concrete durability
Editor(s): D. Bjegović, H. Beushausen, M. Serdar
ISBN: 978-2-35158-135-3
e-ISBN: 978-2-35158-136-0
Pages: 225 - 232
Total Pages: 8
Language: English

Abstract: 
Corrosion creates long term reliability issues for reinforced concrete structures. Billions of dollars have been spent on corrosion protection of concrete and steel bridges, highways, and reinforced concrete buildings. Among the commercial technologies available today, migrating corrosion inhibitors (MCIs) show versatility as admixtures, surface treatments, and in rehabilitation programs. The effectiveness of the MCIs (mixture of amine carboxylates and amino alcohols) on reinforced concrete was evaluated throughout this project. Corrosion test results conducted over 1500 days, 200 cycles per ASTM G109) using immersion and ponding in 3.5% NaCl solution indicated that polarization resistance (Rp) for the MCI coated concrete was higher (60-80 kohms-cm² with increasing trends) than non-coated concrete. The untreated not only had lower Rp values, but also decreasing trends. Examination of the embedded steel rebar after corrosion tests showed no corrosion attack for the MCI treated concrete samples, while non treated concrete showed corrosion. X-ray photoelectron spectroscopy (XPS) and depth profiling confirmed that the inhibitor had reached the rebar surface in less than 150 days. Depth profiling showed an amine rich compound on the rebar surface that corresponded with the increase in Rp and improved corrosion protection for the MCI treated steel rebar even in the presence of chloride ions. Based on measured corrosion rate the life expectancy of a concrete reinforced structure can be improved by more than 40 years.

Online publication: 2013
Publication Type: full_text
Public price (Euros): 0.00