Overview

• A study by Chalmers University of Technology reveals that seawater intrusion fosters bacterial biofilms, which erode tunnel concrete at measurable rates.
• Concrete degradation rates reach up to 1 cm per year and can penetrate as deep as 10 cm within five years under extreme conditions.
• The natural aging of concrete lowers its pH, creating an environment conducive to bacterial growth and accelerating corrosion processes.
• Researchers discovered previously unknown microorganisms, including new bacterial families, offering insights into microbial activity and bio-corrosion mechanisms.
• Norwegian authorities maintain that tunnels remain safe under continuous monitoring and recommend proactive maintenance to mitigate risks.