Concrete infrastructure, such as bridges, roads, and parking structures, are the backbone of modern urban and industrial development. However, these structures face significant deterioration due to environmental exposure, including harsh winters, road salt, and moisture. One of the most challenging issues is corrosion, especially when chloride-based deicers are used during winter months. Magnesium chloride, a widely used deicer, has raised concerns about its potential to accelerate corrosion in concrete structures. However, with careful management and understanding of its properties, magnesium chloride can play a pivotal role in maintaining concrete infrastructure, offering both advantages and challenges.
At SHNChem, we specialize in magnesium chloride production and distribution, supplying high-quality products for a wide range of industrial and maintenance applications. In this article, we will explore how magnesium chloride impacts concrete infrastructure, its potential effects on corrosion, and how it can be effectively managed to prolong the life of concrete structures.
Corrosion in concrete primarily affects the steel reinforcement bars (rebar) embedded within the structure. Concrete itself is a durable material, but the steel inside is vulnerable to corrosion when exposed to chlorides, oxygen, and moisture. The corrosion process leads to the formation of rust, which expands and causes cracking, spalling, and deterioration of the concrete.
Chlorides, commonly found in deicers like sodium chloride and magnesium chloride, are known to penetrate the porous surface of concrete. Once inside, they accelerate the corrosion of steel reinforcement, compromising the structural integrity of the concrete. This presents a serious maintenance challenge, especially in regions where deicing is essential for winter safety.
Magnesium chloride (MgCl₂) is one of the most commonly used deicers due to its effectiveness at lower temperatures and reduced environmental impact compared to sodium chloride (NaCl). It is effective at temperatures as low as -15°C (5°F), making it a preferred choice for colder climates. Magnesium chloride's hygroscopic properties (its ability to absorb moisture from the air) help it stay on the road longer, providing extended deicing action.
However, while magnesium chloride is less corrosive to vehicles and road surfaces than traditional rock salt (sodium chloride), it can still pose risks to the steel reinforcement in concrete structures. When applied to roads, magnesium chloride can penetrate concrete surfaces and, over time, accelerate the corrosion of rebar within the structure.
Given its essential role in winter maintenance, magnesium chloride is unlikely to be phased out in cold regions. Instead, effective strategies are needed to balance its deicing benefits with its potential risks to concrete infrastructure. Here’s how magnesium chloride can be managed to reduce corrosion risks while maintaining its effectiveness as a deicer:
One approach to reducing the corrosive impact of magnesium chloride is to add corrosion inhibitors to deicing solutions. These inhibitors help to reduce the penetration of chlorides into the concrete, providing an extra layer of protection for the embedded steel reinforcement.
At SHNChem , we provide magnesium chloride blends that include corrosion inhibitors, reducing the impact on concrete infrastructure while maintaining deicing efficiency.
Concrete surfaces exposed to deicers should be treated with sealants or waterproofing agents that prevent the penetration of chlorides. Properly sealed concrete can significantly reduce the ingress of moisture and chlorides, minimizing the potential for corrosion.
Regular application of these protective coatings ensures that concrete remains impermeable, even during harsh winter conditions when magnesium chloride is in use.
Infrastructure exposed to deicers must undergo routine inspection and maintenance to identify early signs of corrosion or damage. Crack repair, surface refinishing, and reapplication of sealants are essential steps to prevent chloride penetration and subsequent corrosion.
Monitoring chloride levels in concrete can also help determine whether magnesium chloride application is contributing to corrosion, allowing for more targeted maintenance.
Ensuring that magnesium chloride is applied correctly can minimize its impact on concrete infrastructure. Applying the right amount of deicer based on weather conditions can prevent overuse and reduce the potential for excess chloride buildup in concrete.
At SHNChem, we emphasize best practices for application in order to maximize deicing efficiency while minimizing long-term infrastructure damage.
Ongoing research into deicer formulations is improving the safety and performance of magnesium chloride. New blends aim to maintain deicing effectiveness while reducing corrosive impact on concrete and steel reinforcements. These innovative solutions can further enhance the longevity of concrete infrastructure without compromising winter road safety.
In addition to its impact on infrastructure, magnesium chloride is considered more environmentally friendly than sodium chloride. Magnesium chloride has lower levels of harmful runoff and is less toxic to surrounding vegetation and aquatic life. By managing its corrosive properties through inhibitors and proper application, magnesium chloride provides a safer alternative for both infrastructure and the environment.
Magnesium chloride is an effective and widely used deicer that plays a crucial role in maintaining road safety during winter months. However, its impact on concrete infrastructure, particularly its contribution to corrosion of steel reinforcements, requires careful management. At SHNChem, we offer high-quality magnesium chloride products that include corrosion inhibitors, helping to mitigate the risks associated with chloride exposure while maintaining the benefits of effective deicing.
By employing protective measures such as sealing concrete surfaces, conducting regular maintenance, and optimizing deicer application, the long-term impact of magnesium chloride on concrete infrastructure can be significantly reduced. With the right approach, magnesium chloride can continue to serve as an essential tool in winter maintenance while preserving the structural integrity of vital infrastructure.
Q: How does magnesium chloride affect concrete infrastructure?
A: Magnesium chloride can penetrate concrete surfaces and accelerate the corrosion of steel reinforcements (rebar) within the structure. Over time, this corrosion leads to cracking, spalling, and deterioration of the concrete. However, with proper management, the risks can be minimized.
Q: Can corrosion inhibitors be added to magnesium chloride deicers?
A: Yes, corrosion inhibitors can be added to magnesium chloride deicers to reduce the impact on concrete and steel reinforcements. At SHNChem, we offer magnesium chloride blends with added corrosion inhibitors to protect infrastructure.
Q: Is magnesium chloride safer for the environment compared to sodium chloride?
A: Magnesium chloride is considered more environmentally friendly than sodium chloride. It produces less harmful runoff and is less toxic to plants and aquatic ecosystems. Proper management further minimizes its environmental impact.
Q: How often should concrete surfaces exposed to magnesium chloride be inspected?
A: Concrete surfaces exposed to deicers like magnesium chloride should be inspected annually or bi-annually, depending on the level of exposure. Regular inspections help identify early signs of corrosion and damage, allowing for timely maintenance.
Q: What temperature is magnesium chloride effective as a deicer?
A: Magnesium chloride is effective as a deicer at temperatures as low as -15°C (5°F), making it a reliable option for use in colder climates where other deicers may be less effective.
