Optimised Cathodic Protection Design for Maximum Bond Performance in Reinforced Concrete

Reinforced concrete structures in marine and chloride-rich environments face a persistent challenge: corrosion of embedded steel reinforcement. Left untreated, corrosion can reduce structural performance, shorten service life, and lead to costly repairs or premature replacement.

That’s why we were pleased to contribute to the research paper:

“Optimised cathodic protection design for maximum bond performance in reinforced concrete” by Fin O’Flaherty, Chinh Van Nguyen, Paul Lambert, Pal Mangat, and Graeme Jones.

The study explores how impressed current cathodic protection (ICCP) can be optimised to maximise long-term durability while preserving the critical bond between steel reinforcement and concrete.

Why Bond Performance Matters

In reinforced concrete, the bond between steel and concrete is essential. It allows the two materials to work together structurally. If corrosion progresses unchecked, that bond can eventually deteriorate, reducing structural reliability and service life.

Cathodic protection is already recognised as one of the most effective methods of controlling reinforcement corrosion. However, there has historically been concern that excessive cathodic protection current densities could negatively affect the steel-to-concrete bond over long periods of time.

This research set out to answer an important practical question:

Can ICCP systems be designed to provide long-term corrosion protection without compromising bond performance?

What the Research Investigated

The study examined 16 reinforced concrete pull-out specimens with varying levels of pre-corrosion:

  • 0% corrosion (control)
  • 1% corrosion
  • 2% corrosion
  • 5% corrosion

Different ICCP current densities were then applied, including levels significantly higher than those normally used in practice. These accelerated conditions allowed the team to simulate decades of long-term performance within a practical laboratory timeframe.

The researchers analysed:

  • Bond strength between steel and concrete
  • Total electrical charge applied over time
  • Chloride migration away from reinforcement
  • Long-term implications for design life

Key Findings

1. ICCP Can Be Optimised Without Reducing Design Bond Strength

2. Moderate Corrosion Can Temporarily Increase Bond

3. ICCP Helps Reduce Chloride Concentration Around Steel


Why This Matters for Infrastructure Owners

For bridge owners, marine asset operators, and infrastructure managers, the findings support a more performance-based approach to cathodic protection design.

Rather than simply applying higher currents for additional protection, the research demonstrates the value of:

  • Optimised current density selection
  • Long-term total charge assessment
  • Balancing durability with structural performance
  • Extending asset life while minimising unintended side effects

The work also supports more sustainable infrastructure management by helping existing reinforced concrete assets remain in service for longer.

Industry Relevance

The findings are particularly relevant for:

  • Coastal bridges
  • Marine structures
  • Jetties and ports
  • Sea defences
  • Parking structures
  • Chloride-contaminated reinforced concrete assets

As infrastructure owners increasingly focus on whole-life performance and resilience, optimised ICCP design becomes an important tool in extending operational life safely and efficiently.

Get in touch with any questions, queries or potential projects.