Cortec® Corporation, the home of MCI® Technology, is pleased to announce its new, improved MCI®-2040 High Performance Vertical/Overhead Repair Mortar. This is yet another component of Cortec’s High Performance Repair System (HPRS®), which helps concrete repairs last longer by inhibiting corrosion and reducing the risk of the insidious ring-anode effect. With MCI®-2040, Cortec® has extended the protective qualities of MCI®-2041 (horizontal repair mortar) to vertical and overhead surfaces, giving concrete contractors an MCI® repair mortar for any angle!
Extend Service Life of Concrete Repairs
MCI®-2040 is a single-component, fast-setting, high-strength, cement-based repair mortar that is enhanced with Migrating Corrosion Inhibitors (MCI®). MCI®-2040 offers corrosion protection to reinforcing metals both in the patch and in the surrounding areas. Migrating Corrosion Inhibitors in the concrete repair mortar penetrate the substrate and even out corrosion potentials between patched areas and nearby concrete. This slows down the ring-anode/halo effect in surrounding concrete. Once applied and hardened, MCI®-2040 provides a high level of adhesion and durability, as well as resistance to water and carbonation attack. This increases the quality and extends the service life of the repair and surrounding structure.
More Flexibility for Vertical and Overhead Repairs
MCI®-2040 is an easy-to-handle patching material for fast-paced repair jobs. It offers quick turnaround due to high early strength and can be applied like normal repair mortars, but without the need for bonding agents. MCI®-2040 is specifically designed for vertical and overhead repairs, greatly increasing the potential use for MCI® repair mortar and offering enhanced flexibility for contractors. Possible applications for MCI®-2040 include the following:
Undersides of bridge decks, parking ramps, balconies, and ramps
Concrete columns, retaining walls, building facades, and soffits
MCI® High-Performance Repair System (HPRS®)
For best results, MCI®-2040 should be applied following the five steps of the MCI® HPRS®:
Prepare the substrate.
Treat and clean rusted rebar in concrete.
Apply repair materials (e.g., MCI®-2040) to reinstate concrete and mitigate rebar rust.
Apply surface applied corrosion inhibitors (optional for added protection).
Apply final coating (optional for added protection).
The HPRS® guide promotes maximum repair mortar success through best practices for surface prep (critical to good adhesion) and additional protection options.
Building and Resource Conservation
Sustainability has become a buzzword in today’s construction market with practical implications for building owners as well as the environment. Engineers are looking for ways to make buildings last longer to meet increasing service life demands and preserve an aging infrastructure. However, in spite of the strength of concrete as a durable building material, repairs are an inevitable part of the concrete life-cycle. The good news is that the proper use of MCI® Technology to mitigate concrete corrosion can help concrete structures and repairs last longer, ideally lengthening intervals between repairs and thus saving substantial time, labor, and money. Contact Cortec® to learn more about the benefits of MCI®-2040 for vertical and horizontal repairs: https://www.cortecmci.com/contact-us/
Keyword: rusted rebar in concrete, rebar rust, Migrating Corrosion Inhibitor, concrete corrosion, corrosion inhibitors in concrete, MCI concrete, repair rusted rebar concrete, Cortec, From Grey to Green, sustainability
The ubiquitous problem of rebar rust is hard to escape in the construction industry, but there is a practical answer. As part of Cortec’s High Performance Repair System (HPRS®), CorrVerter® MCI® Rust Primer simplifies surface prep by passivating corrosion on steel surfaces. It is an exciting tool to help the construction industry tackle a recurring challenge.
The Problem of Rebar Rust
Rebar and other reinforcing metals play an integral role in providing the strength necessary to make concrete a viable building material. It is also one of the major causes of concrete deterioration. Although the high initial pH of concrete creates a naturally passive environment that protects metal reinforcement in new concrete, carbonation and cracking can lead to the formation of corrosion products on embedded reinforcement. As rebar rusts, it expands, putting pressure on the concrete cover. This causes more cracking and concrete spalling, deteriorating the structure and eventually requiring repair.
Effective Concrete Repair
For a repair to be effective, exposed reinforcement is typically sandblasted to remove corrosion and promote good surface adhesion to the new repair material. The ICRI 310.1R-2008 “Guide for Surface Preparation for Repair of Deteriorated Concrete Resulting from Reinforcing Steel Corrosion,” states that exposed reinforcing steel should be free of any materials such as concrete, dirt, and corrosion products that could interfere with repair material adhesion, although tightly bonded light rust is usually not detrimental to the bond of patch materials. This opens the door to a completely different level of surface prep convenience using CorrVerter® MCI® Rust Primer.
How CorrVerter® MCI® Works
CorrVerter® MCI® is a unique formulation of chelating agents combined with a high-solids waterborne latex with extremely low water vapor permeability. This fast drying, single-component primer converts surface rust into a hydrophobic passive layer and offers excellent protection against re-rusting of metal surfaces. These characteristics are ideal for repairs, making surface prep extremely simple. When using CorrVerter® MCI, the first step is to wire brush loose rust off the metal surface. This requires much less labor than blasting and no special equipment. The next step is to remove the excess salt, dust, and contamination by rinsing with water. CorrVerter® MCI® can then be applied by spray or brush and left to cure for 12 hours before applying repair products. CorrVerter® will turn visibly black by the time it dries to touch in about two to three hours.
A Convenient Solution for the Construction Industry
CorrVerter® MCI® is an exciting labor- and time-saving tool for contractors and engineers to be aware of. In addition to increasing the convenience of concrete repairs, CorrVerter® MCI® is also useful for construction delays where some concrete was already poured, leaving rebar partially exposed to the elements until the project can resume. When the project starts again, CorrVerter® MCI® is a good way to passivate any rust that has begun in the meantime, thus forestalling additional corrosion problems that could develop as a result. Contact Cortec® to learn more about these great alternatives to sandblasting during concrete repair and rusty surface prep: https://www.cortecmci.com/contact-us/
Keywords: rusted rebar in concrete, surface prep, rebar rust, construction industry, concrete deterioration, concrete repair, Cortec, MCI, concrete spalling, alternative to sandblasting
When it comes to sustainability, the most important thing Cortec® MCI® Technology can do is to help extend the service life of reinforced concrete structures by mitigating corrosion. Because concrete is a major producer of greenhouse gas, the very act of helping concrete last longer means less new concrete is needed to replace the old concrete, thus reducing overall CO2 output from cement production. Furthermore, MCI® helps contractors and building owners steward resources wisely by repurposing existing structures and sometimes even using renewable materials for construction.
Challenges to Concrete Service Life
To understand MCI’s impact on sustainability, it is necessary to look at one of the major challenges to concrete longevity: corrosion. The two main sources of corrosion in concrete are chlorides and carbonation. For example, a structure with high chloride exposure from proximity to the sea or frequent exposure to deicing salts is likely to corrode much sooner than a reinforced concrete structure in the middle of a dry, landlocked environment. However, even structures in this latter environment can deteriorate over the years as carbonation sets in from exposure to CO2 in the air. Carbonation reduces the naturally high pH of the concrete so that reinforcement is no longer in the zone of passivity and can corrode more easily. In either case, concrete cracking can make matters worse by allowing corrosives to enter and reach reinforcing steel more quickly.
Helping Concrete Structures Last Longer
MCI® Technology can protect against both types of corrosion by forming a protective molecular layer on the surface of the steel reinforcement. By interfering with the natural corrosion reaction between oxygen, steel, and an electrolyte, MCI® delays time to corrosion and reduces corrosion rates once started. MCI® can be applied as a concrete admixture to new structures or as a surface applied corrosion inhibitor (SACI) to existing structures. It can also be combined with repair mortars or water repellents for dual benefit and application convenience. In this way, both specifying engineers and repair contractors can help their work last longer and be more efficient, reducing the time and labor normally needed for repair. This weighs strongly in favor of earning credits toward LEED certification, a prominent sustainability rating system overseen by the U.S. Green Building Council.
Earning LEED Credits
Earning LEED credits with MCI® can take a two-pronged approach. The main area in which MCI® can help in LEED v4.1 Building Design + Construction is under the credit category of “Building Life-Cycle Impact Reduction,” which looks at “Building and Material Reuse,” as well as the “Whole-Building Life-Cycle Assessment.” By specifying MCI® admixtures in new structures, engineers can reduce the need for concrete repairs and reconstruction to achieve the same service life, thus reducing overall CO2 output over time. In a similar vein, MCI® repair products can help existing structures last longer, thus making it possible to reuse resources that have a high embodied carbon output (carbon emissions from building the structure) instead of demolishing and replacing them. Another way that contractors can earn credits toward LEED certification is by using MCI®-2005, a corrosion inhibiting concrete admixture that protects against both chloride- and carbonation-induced corrosion. MCI®-2005 is a USDA Certified Biobased Product derived from corn. It contains 67% USDA certified biobased content and can contribute to the “Responsible Sourcing of Raw Materials” LEED credit category.
Building for Coastal Resilience
There are many examples of how MCI® has been used in efforts to extend service life by delaying or mitigating corrosion on rusted rebar in concrete. The Lodge at Gulf State Park is an excellent model. Replacing the original lodge that was destroyed by Hurricane Ivan, the new lodge was designed with special goals for sustainability and resilience. A corrosion mitigation strategy was especially important given the corrosive location of the hotel on the Gulf Coast. In addition to MCI®-2005 being a biobased product in line with the project’s overall goal of LEED certification, MCI®-2005 was also shown to outperform the service life of epoxy-coated rebar (intended for corrosion protection) in service life prediction modeling. Furthermore, it provided significant direct cost savings to the project.
Structural Reuse vs. Concrete Demolition
The Höganäs County Water Tower is an excellent example of how MCI® repair materials can be used to restore and prolong the service life of existing structures rather than demolishing them. Although built for a service life of 50 years, the water tower was already deteriorating at age 42, with chunks of concrete falling off due to chloride- and carbonation-induced corrosion. The concern was that additional damage could develop quickly and affect structural integrity. The municipality therefore requested a repair strategy that would provide 20 additional years of service life. The project owners settled on a repair plan that included MCI®-2020 V/O for corrosion mitigation over other proposals that had a shorter expected service life or required demolition.
Meeting Longer Service Life Demands
The sustainability trend is evidenced in the fact that more and more projects are demanding structural service lives of 100 years or more. This is the case of the new Pelješac Bridge, which creates an important link between two separate parts of Croatia. The bridge was designed to have a 130-year service life and therefore incorporated multiple corrosion mitigation strategies to counteract concrete corrosion in the harsh saltwater environment. One of these strategies was the application of MCI®-2018 onto the concrete pylons. This supplied the concrete surfaces with a 100% silane water repellent (to block intrusion of corrosives) and Migrating Corrosion Inhibitors to penetrate and protect embedded steel reinforcement.
An Important Key to Sustainable Construction
The need for concrete corrosion solutions will only get stronger as service life demands increase and sustainability requirements get stricter. MCI® Technology provides a convenient, efficient, and effective method of corrosion protection for both new and existing structures, providing an important key to sustainable construction and the long-term reduction of one’s carbon footprint. Contact Cortec® to learn more about MCI® and sustainable construction: https://www.cortecmci.com/contact-us/
Keywords: extend service life, From Grey to Green, sustainable construction, Cortec MCI, LEED credits, sustainability, concrete admixture, concrete corrosion, carbon footprint, rusted rebar in concrete
Cortec® Corporation is the global leader in innovative, environmentally responsible VpCI® and MCI® corrosion control technologies for Packaging, Metalworking, Construction, Electronics, Water Treatment, Oil & Gas, and other industries. Our relentless dedication to sustainability, quality, service, and support is unmatched in the industry. Headquartered in St. Paul, Minnesota, Cortec® manufactures over 400 products distributed worldwide. ISO 9001:2015, ISO 14001:2015, & ISO/IEC 17025:2017 certified. Cortec® Website: http://www.cortecvci.com Phone: 1-800-426-7832 FAX: (651) 429-1122
The concept of value engineering is not only for the construction phase. It is also a useful practice during the maintenance and repair stages of existing reinforced concrete structures, ensuring projects get done within budget. True value engineering saves money without reducing service life or affecting the quality of construction or materials. Ideally, it adds value to the project. MCI®-2019 is one such value engineering solution to take advantage of when seeking to extend the service life of existing concrete structures.
The Benefit of MCI® Water Repellents
MCI®-2019 is a 40% silane, solvent-based concrete water repellent containing Migrating Corrosion Inhibitors. The small molecules of MCI®-2019 can easily penetrate into concrete, providing water repellency by chemically reacting with cementitious substrates under proper application. MCI®-2019 seals surface pores, which prevents intrusion of chloride and carbonation and protects from the ingress of wind driven rain. Treated areas retain their original appearance and are breathable. MCI®-2019 is an excellent option both as the finishing touch on a concrete repair (where no membrane or coating system is used) and for periodic maintenance every 7-10 years. Since MCI®-2019 increases service life, it can ultimately reduce the use of repair or reconstruction materials, thus contributing to sustainability.
Coping with Silane Shortages
One of the big challenges for the construction industry and many others today is the issue of raw material shortages (consequently driving the cost of materials up). For instance, silane supplies are often delayed or difficult to find. Using only a 40% silane relaxes the demand and helps the supply go farther while still providing a significant degree of water repellency. Since MCI®-2019 contains Migrating Corrosion Inhibitors that provide active corrosion protection at the rebar, the need for 100% silane is also not as strong because a dual mechanism is at work to keep corrosives out and resist those that do find their way in.
In addition to working around supply chain shortages, MCI®-2019 is also a great way to help cut costs when working on a limited budget. This is especially true with the current combination of supply chain shortages and inflation driving up the price of silane even farther. Using MCI®-2019 saves costs compared to similar alternative systems. It can help a project stay within budget while still offering an excellent source of corrosion protection.
Saving Labor Time and Intensity
Another way MCI®-2019 can save costs is simply by requiring less labor than other water repellents and surface applied corrosion inhibitors (SACIs). Silane wears out and erodes over time, so a good maintenance practice is to reapply it at 7–10-year intervals to maintain concrete water resistance and simultaneously add another dose of SACIs. Usually, workers water-blast the surface to make sure the silane residual is completely cleaned off and then apply a new SACI and a 100% silane water repellent. However, with MCI®– 2019, this may be unnecessary. Workers can save time by applying one or two coats of a two-in-one product and leaving the old silane in place. The silane in MCI®-2019 supplements any residual silane, while Migrating Corrosion Inhibitors are still able to penetrate into the concrete. A further advantage is that MCI®– 2019 does not etch, stain, discolor, or otherwise harm glass or aluminum.
Repair of University Towers
In 2015, three 1970’s cast-in-place concrete residence towers at a Midwestern university required repair due to rusted rebar in concrete. After using MCI®-2019 instead of a standard 40% solids silane water repellent post repair, the project’s specifying engineer commented, “MCI®-2019 provided a cost-effective solution in applying both a migrating corrosion inhibitor and a silane sealer in a single product in one application with no resulting color change to concrete façade[s].” The non-etching feature was crucial to the protection of the structure’s new windows, and the parties involved were happy with the ease of MCI®-2019 application.
Be Ready with Multiple Value Engineering Solutions
In today’s market, it is important to have many different value engineering options at one’s fingertips. MCI®-2019 is one that can help engineers and contractors cope with silane shortages and stay within budget all while fortifying concrete with corrosion inhibitors to extend service life. Contact Cortec® to discuss this and other value engineering solutions for your construction and repair projects: https://www.cortecmci.com/contact-us/
Keywords: value engineering, concrete maintenance, concrete repair, extend service life, sustainability, raw material shortage, rusted rebar in concrete, Cortec MCI, From Grey to Green, surface treatment
Cortec® Corporation is the global leader in innovative, environmentally responsible VpCI® and MCI® corrosion control technologies for Packaging, Metalworking, Construction, Electronics, Water Treatment, Oil & Gas, and other industries. Our relentless dedication to sustainability, quality, service, and support is unmatched in the industry. Headquartered in St. Paul, Minnesota, Cortec® manufactures over 400 products distributed worldwide. ISO 9001:2015, ISO 14001:2015, & ISO/IEC 17025:2017 certified. Cortec® Website: https://www.cortecvci.com Phone: 1-800-426-7832 FAX: (651) 429-1122
With rising inflation, material shortages, and the ever present demand of staying within budget, engineers and construction companies today are increasingly turning to the concept of value engineering. One important facet of this effort is safely finding ways to extend the useful service life of existing structures. When it comes to maintenance and repair, silane shortages and rising prices are making life more difficult for building owners and engineers. In light of these constraints, Cortec’s MCI®-2020 technology has become an especially important resource for value engineering at this time.
Dealing with Silane Shortages
One of the big issues engineers and building owners have recently had to deal with is a shortage of silane. Supplies are more difficult to find and more expensive. This is a big obstacle for the construction and building maintenance industry, which has typically relied on silane products for concrete water-repellency. Silane is used to limit the ingress of corrosives and is often applied during routine maintenance or at the end of a concrete repair. Contractors currently either have to swallow a higher price for the limited silane available or find other ways to protect structures from corrosion.
An excellent alternative is MCI®-2020, a Migrating Corrosion Inhibitor™ surface treatment designed to penetrate through cementitious materials including concrete, mortar, and limestone. It provides corrosion protection against carbonation, chlorides, and other contaminants. Although it does not include water repellency like some other surface applied corrosion inhibitors (SACIs), it introduces a stronger concentration of Migrating Corrosion Inhibitor™ to reduce corrosion rates of rusted rebar in concrete. By itself, this can have a powerful impact on the longevity of the building. However, MCI®-2020 can also be followed by any water-repellent or coating system to maximize and even enhance concrete corrosion protection in the wake of silane shortages.
Reducing Time and Labor Costs
Another reason MCI®-2020 is an important resource for value engineering is its overall cost- and labor reducing characteristics compared to other methods of corrosion protection for existing structures. For example, installing sacrificial anodes is a common method of protecting corrosion “hot spots” when performing concrete repairs. The technology works, but only if the rebar has a continuous connection to the anode. Installation is time- and labor-intensive, requiring workers to drill or chip out parts of the concrete in order to install hundreds or thousands of anodes for a typical job. To make matters worse, anodes become depleted over time and often have to be reinstalled within 10 years, requiring more excavation and repair of the concrete cover.
In contrast, MCI®-2020 is easy to apply by spray, brush, or roller to a clean concrete surface in one to two coats. It also happens to be one of the easiest SACI products on the market to apply and has the highest concentration of corrosion inhibitor. Unlike most other SACIs, MCI®-2020 requires fewer coats and less wait time between coats. It is also easier to clean (e.g., water rinse only) before applying a topical treatment (e.g., coating, water repellent, membrane system) on top.
Mitigating Corrosion on Buildings with Façades
In spite of MCI®-2020’s superior advantages over other concrete corrosion inhibitor solutions, some architecture demands still other value engineering solutions. This is the case with concrete buildings covered by tiling, stone cladding, paint, or other façades that make it difficult if not impossible to apply the SACI to the surface without time consuming and cost-prohibitive façade removal. MCI®-2020 Gel allows engineers and repair workers to inject the corrosion inhibitor to the depth of the rebar by drilling inconspicuous holes at routine intervals. While this process is similar to applying anodes, it is much simpler because it is not necessary to make a direct connection from an anode to the reinforcing steel. The most important advantage, however, is the cost and labor savings from not having to do major deconstruction of the exterior wall in order to apply Migrating Corrosion Inhibitors.
Leveraging Cost-Effective Materials for High Level Returns
In today’s market, specifying engineers and other decision makers must be especially creative and adept at leveraging cost-effective materials and strategies for high level returns on structural safety, longevity, and sustainability. When it comes to mitigating corrosion to extend the service life of existing concrete structures, Cortec® MCI®-2020 and MCI®-2020 Gel offer excellent value for cost. Contact Cortec® MCI® today to discuss these and other value engineering solutions: https://www.cortecmci.com/contact-us/
Keywords: value engineering, cutting costs, extend service life, silane shortages, surface treatment, concrete repairs, corrosion protection, sacrificial anodes, Cortec MCI, From Grey to Green
In this day and age of inflation, supply chain delays, and raw material shortages, value engineering is becoming more and more important as a way to cope with out-of control market factors. Construction industry engineers are looking for alternative materials to compensate for shortages and higher prices.
At the same time, there is increasing concern about being safe, extending service life, and enhancing sustainability. How do engineers meet these demands while staying sane and within budget? Migrating Corrosion Inhibitor™ (MCI®) Technology is an excellent answer for maximizing sustainability and service life while balancing cost considerations in these unpredictable times.
Extend Service Life at a Fraction of Total Cost When it comes to construction, engineers can enhance sustainability by extending the service life of new concrete structures. This reduces the need to replace existing concrete, thus minimizing carbon output since cement production is a large contributor to global greenhouse gas emissions. Corrosion inhibiting admixtures are one way to enhance longevity from the start of a project by counteracting the deteriorating effect of carbonation, chlorides, and corrosives that cause rusted rebar in concrete. For example, MCI®– 2005 and MCI®-2005 NS are two MCI® concrete admixtures that delay time to corrosion and reduce corrosion rates once started by forming a molecular protective layer on the rebar surface. This is especially important where exposure to seaside environments, winter deicing salts, and sabkha soil is expected. It can also be important as a structure ages and carbonation sets in, reducing the naturally protective high alkalinity of the concrete.
It is further important to note that MCI®-2005 and MCI®-2005 NS can significantly increase the
estimated service life of a structure at a small fraction of total construction costs. For example, one service life prediction estimated that using MCI®-2005 in the podium substructure of the Princess Tower in Dubai would extend service life from 48 years to 103 years. This was at 0.07% of the total construction cost.
MCI® Technology vs. Calcium Nitrite MCI®-2005 and MCI®-2005 NS also have advantages when compared to other strategies of corrosion mitigation. For instance, they are great alternatives to
calcium nitrite (CNI) admixtures, the go-to corrosion inhibiting admixtures for decades. Some of the advantages of MCI®-2005 and MCI®-2005 NS are that they contain renewable materials, do not accelerate set time, have a fixed dosage rate, and are certified to meet NSF Standard 61 for use in potable water structures. In contrast, CNI is an inorganic, non-biobased chemistry that can be difficult for ready-mixers because it works as a set accelerator. It is not certified to meet NSF Standard 61, and it requires a higher dosage rate that increases based on expected chloride loading. It is not effective against carbonation corrosion.
At first glance, CNI appears to be less expensive than MCI® due to a lower price per gallon. However, the true cost is hidden behind the dosage rate, which can be 2.0 or more gallons per cubic yard (10 L/m³), depending on expected chloride loading. MCI®–
2005/2005 NS is more economical than CNI in almost all cases because it is dosed at a fixed rate of 1.0-1.5 pints per cubic yard (0.6-1.0 L/m³). A recent parking garage project brings this cost comparison into focus. The garage required enough admixture for 20,000 cubic yards (15,291 m³) of concrete. The estimated cost savings by using MCI® was 14% when compared with the price of CNI dosed at 2.0 gallons per cubic yard (10 L/m³). At higher dosages (e.g., 4.0-6.0 gallons per cubic yard [20-30 L/m³]), the cost savings would have soared to between 129% and 243%. Furthermore, the use of CNI may require a higher dose of air-entraining agents or the addition of set-retarding or shrinkage-compensating admixtures. This is not required when using MCI®, making room for additional savings.
MCI® Technology vs. Epoxy Coated Rebar Another common strategy to mitigate corrosion and extend service life is to use epoxy coated reinforcing steel. The major challenges are high cost and vulnerability to corrosion where the epoxy coating has chipped. Interestingly, MCI® can offer substantial cost savings and service life advantages. For example, the recently constructed Lodge at Gulf State Park was initially specified to use epoxy coated rebar. However, due to budget constraints and a better service life prediction with MCI®, the specifying engineer ultimately settled on MCI®-2005 admixture instead. As a result, the project saved six figures and incorporated a biobased product that could help earn credit toward LEED certification.
Value Engineering with MCI® The comparative advantage goes on. Some designers have used MCI® to reduce the concrete cover requirements while achieving the same service life estimates, which consequently allowed them to reduce the amount of steel reinforcement to control concrete cracks. In some cases, this allowed for a seven-figure savings in the total cost of the project. The important point is that, by evaluating MCI® next to other materials and strategies, engineers can find the best cost benefit ratio for their structures in the construction, repair, and maintenance phases. Contact Cortec® for an MCI®/CNI cost comparison and more strategic ideas on value engineering with MCI®: https://www.cortecmci.com/contact-us/
Keywords: value engineering, sustainability, MCI, concrete admixtures, rusted rebar in concrete, extend service life, increasing inflation, raw material shortage, From Grey to Green, Cortec
On 26 of July, Pelješac Bridge, the largest ever EU infrastructure investment in Croatia, officially opened in grand ceremony. The bridge, providing a road link between two parts of the country is of strategic importance and is one of the most substantial EU infrastructural investments ever. It connects the region of Southern Dalmatia with the rest of the country’s mainland. The bridge will cut travel time by 37 minutes along the Adriatic coastline, improving people’s lives and increasing economic opportunities for the region. It has 13 spans, five of which are 285 meters long, six centrally placed reinforced concrete pylons with a height of 33 meters, and two lanes together with a stop lane that will serve for bridge maintenance.
Peljesac bridge is ranking among the most demanding bridges in the world—in complexity of construction and design. Bridge is 2,404-m (7,887.14-ft) long. ln order to meet the main criteria of quality design, such as stability, durability, economy and integration into the environment, the design proposed the construction of an extra dosed bridge with an integrated hybrid structure. Structure is comprised of five central spans, each 285-m long, and six low pylons. Especially careful approach was taken to ensure durability for the extended lifespan of over 130 years. Cortec’s MCI® 2018 was specified on this project during the design phase as a silane-based impregnation with a migrating inhibitor property to protect against the harmful effects of corrosion, thus extending the service life of the bridge. MCI® 2018 is a 100% silane-based concrete sealer, containing migrating corrosion inhibitors that allow deep penetration into concrete and provides water repellence by chemically reacting with the cementitious substrate. It seals surface pores, preventing the intrusion of chlorides, reduces carbonation, and protects from the ingress of wind-driven rain. Treated concrete surfaces are fully breathable and their natural moisture-vapor transmission is not affected. After repair of surface damage and cleaning of discolorations and other surface defects, the concrete surface of the pylons needed to be protected with a colorless silane coating to improve durability and increase the resistance of the concrete surface to long-term external influences. MCI®-2018 carries CE certification that indicates conformity with health, safety and environmental protection standards for products sold within the European Economic Area (EEA).
Application of Cortec’s MCI®-2018 A combination of AC coatings, cathodic protection of steel reinforcement in piles and pile heads, a concrete cover of 65–85 mm stainless steel reinforcement and impregnation of all concrete surfaces with MCI®-2018 was selected. This was chosen as the strategy to help the bridge achieve a 130-year service life. MCI®-2018 was applied on the entire substructure of the bridge. All concrete parts were coated with MCI®-2018 by a spraying technique. The work was performed in accordance with the project requirements and after surface preparation to full functionality. This included:
Access to pylons
Rehabilitation of the concrete surface of the pylons
Cleaning the concrete surface of the pylon (washing the pillars with water)
Impregnation of the concrete surface of the pylon with MCI®-2018.
MCI®-2018 contains time-proven Migrating Corrosion Inhibitors (MCI®). The silane component provides water repellency by chemically reacting with the cementitious substrate under proper application, decreasing the ingress of aggressive materials. The product penetrates deep into concrete, providing corrosion protection to reinforcing steel from existing water and chloride ions, or other contaminants. Continuous monitoring of the condition of the structure at one central place was done during the construction phase and will be done at the exploitation phase to examine parameters of structural behavior, time, seismic activity, and structural durability. The designer of the bridge specified corrosion protection for all concrete segments in order to achieve a 130-year service life.
Cortec’s CEO, Boris Miksic, Croatian-American businessman is proud that his patented technology was used on this historic project to connect two parts of his country. “Our MCI® technology is used in largest construction projects throughout the globe. Witnessing its application in my home country on this monumental bridge structure is truly a special. Peljesac bridge is huge step forward for all of us.” A strategic investment such as this bridge, demonstrates European Commission’s commitment to bring people together and unite territories, while reinforcing the territorial cohesion of the region and helping other neighboring countries.
In a world where concrete is the most widely used construction material, the need for concrete repairs is inevitable. This is especially true in corrosive environments where concrete deterioration accelerates due to seawater or heavy use of deicing salts. Since concrete repairs are time and labor intensive, it is important to do them in a way that will extend structural service life as much as possible. Cortec’s new, improved line of MCI® repair mortars is designed to help contractors reach that goal, starting with the release of MCI®-2039 High Performance Horizontal Repair Mortar.
Enhance Repairs with Migrating Corrosion Inhibitors
MCI®-2039 is a single-component, fast-setting, high-strength, cement-based repair mortar enhanced with Migrating Corrosion Inhibitors (MCI®). These inhibitors form a molecular protective layer on the surfaces of rebar, increasing the quality and extending the service life of the repair and surrounding structure. Once applied and hardened, MCI®-2039 provides a high level of adhesion and durability, as well as resistance to water and carbonation attack. High early strength allows for fast repairs and quick return of traffic. MCI®-2039 can be applied indoors or outdoors in a wide temperature range, from 20 to 100 °F (-6 to 38 °C). The mortar can be extended up to 60% by weight for repairs greater than 2” (51 mm) deep.
Minimize the Ring-Anode/Halo Effect
One major problem with concrete repairs is the insidious ring-anode/halo effect. This occurs when the higher pH and resistivity of the patch material creates a difference in corrosion potential between new and old concrete. As a result, corrosion activity may accelerate in the concrete surrounding the patch. What was intended to fix the problem inadvertently shifts the corrosion process to another area. MCI®-2039 can minimize this counterproductive effect as Migrating Corrosion Inhibitors in the repair mortar travel to adjacent concrete to even out the corrosion potential and help the repair last longer.
Implement a High Performance Repair System (HPRS®)
MCI®-2039 is part of Cortec’s MCI® High Performance Repair System (HPRS®), which outlines five steps to achieve long-lasting concrete repairs. The first step is to prepare the substrate following ICRI Guideline No. 310.2R-2013 (or a similar engineering guide). Secondly, rusty rebar should either be blasted to bright metal or coated with CorrVerter® MCI® Rust Primer to passivate the rust. MCI®-2039 is applied next (for horizontal repairs). After the repair mortar has cured, a surface applied corrosion inhibitor (SACI) such as MCI®-2020 (or a water-repellent MCI® SACI) should be used on the entire concrete surface. An optional final coat of MCI® EcoRainbow® Architectural Coating protects against water intrusion and carbonation and provides a finished look.
By following these MCI® HPRS® guidelines, concrete contractors can maximize the durability of the patch and thus delay time to the next repair, substituting MCI®-2039 for standard repair mortar to enhance protection wherever a horizontal concrete repair is needed:
Bridge decks, parking decks, and ramps
Highway repairs and overlays
Slabs below grade, on grade, or above grade
Industrial and commercial structures
Make Repairs Last Longer with MCI®-2039
For anyone looking to enhance the longevity of a concrete repair, MCI®-2039 is a convenient way to add corrosion protection directly into the repair process. Combined with the entire MCI® HPRS®, it is an even more powerful antidote to corrosion decay in reinforced concrete. Contact Cortec® MCI® today to learn about MCI®-2039 and other MCI® enhanced repair products: https://www.cortecmci.com/contact-us/
Cortec® Corporation is pleased to announce the receipt of a Concrete Contractor 2022 Top Products award for CorrVerter® MCI® Rust Primer! Concrete Contractor uses these awards to recognize innovative industry products that have captured the attention of construction professionals who read their magazine or website. In an announcement listing this year’s award winners, the editor of Concrete Contractor explained, “These solutions were designed to not only help overcome the challenges contractors face on a daily basis but do so with innovative ideas and the ingenuity for them to be successful in the years to come.” Here is how CorrVerter® MCI® Rust Primer does that for the concrete industry.
Making Life Easier for Concrete Repair Contractors
CorrVerter® MCI® Rust Primer makes life easier for contractors performing concrete repairs by providing an alternative to grinding and abrasive blasting of rusty rebar. In order to ensure the soundness of a concrete repair, the contractor must make sure that the exposed reinforcing metal will bond properly to the new concrete patch material. The ICRI 310.1R-2008 “Guideline for Surface Preparation for the Repair of Deteriorated Concrete Resulting from Reinforcing Steel Corrosion” calls for a clean metal surface with no concrete, dirt, or corrosion products that could interfere with adhesion, noting that a layer of tightly bonded light rust is usually not a problem. CorrVerter® MCI® Rust Primer falls within these guidelines and circumvents the need for labor-intensive blasting by passivating the rust with rust converting primer.
How CorrVerter® Works on Rusty Rebar
CorrVerter® MCI® is a single component, fast-drying, water-based primer that converts rusted surfaces to a passive layer. It contains a unique formulation of chelating agents combined with a high solids waterborne latex with extremely low water vapor permeability. The combination of these materials converts the surface rust into a hydrophobic passive layer with excellent protection against re-rusting. This is perfect for concrete repair applications where rusty steel reinforcement has been exposed, where further corrosion protection is required, and where good surface prep is difficult to achieve. CorrVerter® is a low-labor alternative to sandblasting and is easy to paint onto corroded rebar after loose rust has been removed with a wire brush. When properly applied, it shows bond strength similar to that of uncoated rebar.
Implementing a High Performance Repair System (HPRS®)
CorrVerter® is an important part of Cortec’s five-step MCI® High Performance Repair System (HPRS®):
Prepare the Substrate
Treat and Clean Rusted Rebars (e.g., apply CorrVerter®)
The MCI® HPRS® is designed to help concrete repairs last longer by incorporating Migrating Corrosion Inhibitors that slow the progression of corrosion and the ring-anode/halo effect. CorrVerter® is a low-labor surface prep option that makes it much easier to get the repair off to a good start.
Honored and Eager to Get Effective Solutions into the Hands of Concrete Contractors
Cortec® is eager to get effective, easy-to-use concrete corrosion protection solutions into the hands of contractors and building owners around the world to extend the service life of reinforced concrete structures. Cortec® is especially honored to be recognized for CorrVerter® MCI® Rust Primer by the Concrete Contractor 2022 Top Products awards and looks forward to continuing to make life easier for concrete contractors with this simple and effective method of rebar surface prep! Learn more about CorrVerter®MCI® Rust Primer here: https://www.cortecmci.com/product/mci-corrverter/
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Extending concrete service life takes a multi-faceted approach, but the underlying principles are always the same: (1) properly understand the conditions and environment, (2) select the appropriate treatment, and (3) apply the chosen solution properly for best results. Many outstanding options exist in Cortec’s line of MCI® Technologies, but not all treatments are equally suited to every application. It is therefore important to know when and why to choose a product such as MCI®-2026 Floor Coating for concrete longevity.
Choosing the Right Product for the Application The first step in selecting a product to extend service life is considering the structure and its environment. For example, an engineer planning a new parking ramp in a harsh winter environment where deicing salts are used could extend service life by specifying Migrating Corrosion Inhibitor™ admixtures for the concrete mix. Workers performing concrete repairs can help the repair last longer by incorporating MCI® Mini Grenades into repair mortars. Facility managers can ward off corrosion on existing structures through periodic application of surface applied corrosion inhibitors (SACIs) such as MCI®-2020. While these products could also be used for concrete floors, often the biggest concern in an industrial environment is the risk of external concrete damage from heavy traffic and exposure to harsh chemicals. It is chiefly after this kind of damage that corrosion is more likely to occur by allowing corrosives to enter the substrate. MCI®-2026 Floor Coating is an excellent first line of defense against these problems.
Benefits of MCI®-2026 Floor Coating There are three main areas where MCI®-2026 Floor Coating is especially helpful:
Applications with strict VOC limits
Federally inspected plants
Areas with heavy traffic and/or chemical spillage
MCI®-2026 Floor Coating addresses the first concern by being a 100% solids, two-component novolac epoxy coating with zero VOCs. This is perfect for maintaining VOC compliance and is a great advantage for workers applying the coating. In the second case, MCI®-2026 meets all USDA/FDA guidelines for use in federally inspected facilities. In regard to the third case, MCI®-2026 Floor Coating achieves a high degree of physical and chemical resistance while maintaining excellent adhesion to properly placed primers. In so doing, it protects concrete surfaces from aggressive industrial environments and prevents the intrusion of corrosive elements that would cause further concrete deterioration at the reinforcement level. MCI®-2026 Floor Coating can be used alone as a body/basecoat or as a topcoat if additional internal moisture resistance is needed by priming the floor below.
Best Practices for Good Concrete Coatings Performance Next in importance to choosing an appropriate technology is applying it properly. As for any coating, good surface preparation is critical to ensuring the best performance possible. Before applying MCI®-2026 Floor Coating, workers should make sure that the concrete floor is clean and sound with a minimum surface profile of CSP-2. Existing coatings should be removed to ensure proper adhesion. As a two-component product (a feature that allows crosslinking for an overall stronger coating chemistry), MCI®-2026 Floor Coating should be properly mixed and applied at the right temperatures per manufacturer’s instructions to work as designed.
Choosing Physical and Chemical Durability for Concrete Floors By choosing to apply MCI®-2026 Floor Coating, facility owners and managers are left with concrete floors with a high degree of physical and chemical resistance. These qualities make the floor more durable and help it last longer primarily by protecting against physical and chemical damage and secondarily by blocking the intrusion of corrosives in an aggressive environment. All this is achieved with a low VOC coating that can be used in federally inspected facilities. Contact Cortec® to see if MCI®-2026 Floor Coating is the right choice for your industrial concrete floor application: https://www.cortecmci.com/contact-us/.
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