APRIL 30, 2012
Transcend Completes VT EPSCoR Project to Evaluate Wireless Corrosion Sensing
Transcendev recently completed a project to evaluate the feasibility of using passive wireless sensors to monitoring for corrosion in concrete bridge decks. The primary cause of reinforced-concrete bridge deterioration is chloride-induced corrosion of the steel reinforcement, resulting in expansion forces in the concrete that produce cracking and spalling of the concrete. The annual direct cost of corrosion for concrete highway bridges is estimated in the billions of dollars.
A non-contact sensing solution could enable direct detection of the onset of corrosion in concrete bridges from a passing vehicle, limiting the need for visual inspections and lane closures, and providing more spatially detailed data.
Transcendev evaluated the feasibility of using passive wireless sensors to directly sense when corrosion is occurring in a bridge deck. The study established a strong correlation between a simple direct sensing modality and mass loss of steel reinforcing bar due to corrosion, evaluated the penetration of radio frequency communication signals into concrete, and measured resonant frequency shifts in passive RFID tag antennae due to the electrical properties of surrounding concrete.
The project was funded by the Vermont EPSCoR program as a subaward under NSF Cooperative Agreement EPS-1101317.