The International Zinc Association (IZA) Africa is one of the proud sponsors of the 7th International Conference on Concrete Repair, Rehabilitation, and Retrofitting (ICCRRR 2024), which takes place from November 4 to 6, 2024, at the University of Cape Town’s Breakwater Campus.

The conference brings together researchers, engineers, infrastructure managers, and technologists from around the world to focus on extending the service life of existing infrastructure and improving the durability of new concrete structures.

One of the key topics under discussion at the event will be the role of zinc galvanized reinforcing steel in concrete, particularly in coastal environments. “Concrete structures, especially those located near the sea, are subject to aggressive environmental conditions that can cause premature deterioration. Zinc galvanized reinforcing steel offers a durable solution that significantly extends the life of these structures,” says IZA Africa Director Simon Norton.

The reinforcement steel within concrete plays a crucial role in the structure’s strength and longevity. However, over time, exposure to moisture, marine salts, and other corrosive elements can lead to the corrosion of unprotected steel, which results in cracking, spalling, and, in extreme cases, structural failure. Zinc galvanized reinforcing steel addresses this issue by providing a protective layer that shields the steel from corrosion.

“Galvanizing steel involves applying a layer of zinc that serves as a sacrificial barrier. When the structure is exposed to corrosive elements, the zinc corrodes first, preserving the integrity of the underlying steel,” says Norton.

Zinc’s ability to function as a sacrificial anode makes galvanized reinforcing steel far more resistant to corrosion than unprotected steel. This characteristic is especially critical for structures built in high-moisture or salt-laden environments, such as those near the sea or close to the coast.

“The primary benefit of using zinc galvanized reinforcing steel is the significant extension of the structure’s service life,” says Norton. By mitigating corrosion, it reduces the need for frequent repairs or costly maintenance, ensuring that concrete structures maintain their integrity for decades.

Structures reinforced with galvanized steel are less prone to cracking and spalling, common issues in environments where corrosion occurs. This not only improves the performance of the structure but also its appearance over time.

Over time, the use of zinc galvanized reinforcing steel translates to fewer interventions, whether for repairs or protective measures. While the upfront cost may be higher, the reduced need for maintenance makes it a cost-effective solution overall for the life of the structure.

Norton stresses the importance of this for projects near the sea. “For structures located less than 10 km from the coast, where salt spray and mist and high humidity present significant risks, zinc galvanized reinforcing steel provides unmatched protection.”

While zinc galvanized reinforcing steel offers various benefits, its effectiveness is dependent on several factors. “In particularly aggressive environments, additional measures may be necessary,” adds Norton. For example, harsher conditions may require supplementary corrosion protection.

Adequate cover over the steel is essential. In coastal regions, Norton advises that the concrete cover should exceed 70 mm to protect the zinc coating. The effectiveness of the zinc coating depends heavily on the quality of the galvanizing process itself. Proper preparation of the steel and adherence to industry standards are critical to ensure optimal protection.

ICCRRR 2024 will provide a platform to delve into the advancements in concrete durability, lifecycle assessments, and smart materials. “For concrete structures near coastal areas, where corrosion is a persistent threat, zinc galvanized reinforcing steel is an invaluable solution. It is not just about extending the life of the structure but about creating more resilient, cost-effective infrastructure for the future,” concludes Norton.

The event will feature technical presentations, keynote addresses, and networking opportunities, including a technical harbour cruise and a conference dinner at a wine farm, offering participants a well-rounded experience in the latest industry advancements.

As global challenges like climate change and ageing infrastructure continue to impact construction projects, zinc galvanizing will become increasingly important in the drive for long-lasting, sustainable building solutions.