Corrosion Mapping Equipment

Half-Cell Potential Tester – COR MAP Corrosion Mapping Equipment

The COR MAP (Half-Cell Potential Corrosion Mapping System) is a non-destructive electrochemical testing instrument for assessing the probability and distribution of active corrosion in reinforced concrete structures. It is used by structural engineers and corrosion specialists on bridges, parking decks, marine structures, and buildings to plan targeted concrete repairs.

Principle

The half-cell potential technique measures the electrical potential between a reference half-cell (typically copper/copper sulphate, Ag/AgCl, or calomel) placed on the moist concrete surface and the embedded steel rebar (connected via a wire). ASTM C876 defines probability thresholds for active corrosion based on the measured potential.

ASTM C876 Probability Thresholds (CSE Reference)

• More negative than −350 mV → >90% probability of active corrosion
• −200 mV to −350 mV → Uncertain corrosion activity
• More positive than −200 mV → >90% probability of no corrosion

COR MAP Features

• Motorised or manual grid scanning over defined survey areas
• Automated potential mapping with grid coordinates recorded
• Colour-coded potential contour maps generated in software
• Multiple reference electrode types supported
• Data exported as Excel, PDF, or direct CAD overlay

Applications

• Pre-repair condition mapping of bridge decks and parking structures
• Marine structure and jetty corrosion surveys
• Carbonation-induced and chloride-induced corrosion assessment
• Forensic investigation of premature concrete deterioration

Standard

ASTM C876, EN 12504-4, IS 13311.

Contact JS Civil Lab Solutions at +91 93596 24761 for pricing and project-specific consultation.