Maximizing the Service Life of Concrete Structures
Reinforced concrete is a common material found in industrial plant foundations,
floors, walls, tanks, and tunnels. Initially, the embedded reinforcement is protected
from corrosion because the pH of new concrete forms a passive layer on the rebar.
However, as time passes, carbonation lowers the pH of the concrete and the passive
layer disappears. The metal reinforcement is then vulnerable to the ingress of
corrosive contaminants—oxygen, moisture, chlorides, and industrial pollutants—
that initiate corrosion. As the corrosion products build on the surface of the rebar,
the resulting pressure creates cracking and spalling of the concrete. This increases
exposure to corrosive elements, and the cycle continues to accelerate structural
Migrating corrosion inhibitors applied as an admixture to new construction or as a
topical treatment to existing structures slow this process down. The migrating inhibitors work their way through the concrete pores by capillary action (when applied as
a liquid) and vapor diffusion, forming a protective molecular layer on the surface of
the rebar. This layer protects at both the anode and cathode of a corrosion cell, significantly reducing corrosion even in the presence of cracking. Migrating corrosion
inhibitors can slow the time to corrosion initiation, dramatically reduce corrosion
rates once started, and extend the projected service life of a concrete structure.
Conclusion: By taking basic steps like these to protect against corrosion and scale,
facilities can help minimize corrosion downtime, increase efficiency, and extend the
lifetime of plant equipment. Vapor phase corrosion inhibitors and migrating corro-
sion inhibitors are important parts of making that happen simply and effectively.
For more information, visit www.cortecvci.com
Cortec Corporation • 4119 White Bear Parkway, Saint Paul, MN 55117, USA
Tel: 800-426-7832 • Email: firstname.lastname@example.org
Circle 51 on Card or http://pen.hotims.com/68942-51
Bionetix_3.25x4.75.indd 1 6/10/15 2:59PM
Figure 3: Migrating corrosion inhibitors travel through concrete to
protect the surface of embedded steel reinforcement. Image Credit:
Cortec Middle East.
Figure 2: CorrVerter simplifies preparation of rusty surfaces. Image Credit: Cortec