A Comparison between Ultrasonic Guided Wave Leakage and Half-Cell Potential Methods in Detection of Corrosion in Reinforced Concrete Decks

Abstract

This article presents the advantages and limitations of a recently developed Ultrasonic Guided Wave Leakage (UGWL) method in comparison to the well-known Half-Cell Potential (HCP) method in their ability to detect corrosion in reinforced concrete (RC) bridge decks. This research also establishes a correlation between UGWL data and chloride content in concrete RC slabs. Concrete slabs submerged in a 10% NaCl solution were monitored using both methods over a period of six months. The chloride content from the three cores (0.84, 0.55, and 0.18%) extracted from the slab after the 6-month long process all exceeded the chloride threshold values suggested in ACI 318, which is 0.05 to 0.1% by weight of concrete. Further, the UGWL method detected changes due to corrosion approximately 21 days earlier than the HCP method.

Keywords

• ultrasonic testing
• ultrasonic guided wave
• half-cell potential
• corrosion
• chloride content
• reinforced concrete bridge decks