Summer is the time for decorative concrete to shine and for concrete contractors to get busy laying and stamping more elegant designs in sidewalks, patios, driveways, and pool decks. But what happens to the beautiful stone, brick, wood, and other decorative concrete patterns imprinted on the pavement several years later when rain, snow, and multiple freeze-thaw cycles begin to take their toll and promote cracking, deterioration, and ultimately rebar corrosion and further cracking? Good foresight and preventative maintenance with Migrating Corrosion Inhibitors and silane water repellents can go a long way toward enhancing the longevity of textured concrete without changing the decorative appearance.
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Corrosion Inhibiting Admixtures for Stamped Concrete
Concrete contractors can get clients off to a good start by encouraging the adoption of a Cortec® MCI® admixture into decorative concrete projects that include rebar or wire mesh. MCI® admixtures are typically more budget-friendly than epoxy-coated rebar for corrosion inhibition and can be added to the concrete mix without the set-accelerating effects of calcium nitrite (CNI) admixtures. This is especially critical for crews that need enough time to stamp designs on the concrete surface before it dries. MCI®-2005 NS is a normal set version, while MCI®-2005 delays set, offering crews more time to apply their decorative imprints. Both have shown good workability among ready-mixers.
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Inconspicuous Routine Maintenance
Once the printed sidewalk or patio is in place, attention shifts to maintenance by facility managers or homeowners. Routine water repellent application is a key part of the process to reduce staining, water ingress, and other deteriorating effects. Corrosion protection for embedded reinforcing metal can be further enhanced by incorporating a dual water repellant / surface applied corrosion inhibitor (SACI) such as MCI®-2018. This 100% silane water repellent is good for use on surfaces where slipping is a concern. Available in both standard and vertical/overhead versions, MCI®-2018 can be applied to decorative concrete without altering its appearance, making it ideal for historical restoration and decorative concrete alike.
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Choosing a Water Repellent for Decorative Concrete
MCI®-2018 molecules penetrate the concrete pore structure, chemically reacting with the cementitious substrate to decrease the ingress of corrosives and forming a protective corrosion inhibiting layer at the surface of the rebar. When only a water repellent is desired, MCI®-2018 X offers the same water-repellency minus the Migrating Corrosion Inhibitors. Application is suggested every seven to 10 years or more frequently as needed. For surfaces where water repellent has been previously applied, MCI®-2019 (with Migrating Corrosion Inhibitors) and MCI®-2019 X (without Migrating Corrosion Inhibitors) offer 40% silane options that reduce the amount of surface prep needed to remove residue from the previous water repellent application.
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Promote the Long-Lasting Beauty of Decorative Concrete
Decorative concrete is an excellent way to get the beauty of stone and brickwork without the extra cost and labor of placing individual pavers. One of the tradeoffs is the importance of maintenance, including special protection against moisture ingress, freeze-thaw cycles, and the corrosion that leads to further cracking. Incorporating MCI® admixtures into the ready-mix is a great way to get decorative concrete off to a good start with extra corrosion protection, while routine maintenance can be enhanced by using two-in-one MCI®/silane surface treatments.
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Prepare to get the most out of your concrete designs by learning more about how Migrating Corrosion Inhibitors fit unobtrusively into the decorative concrete scene: https://www.cortecmci.com/
