Damage to Epoxy Coating on Steel Reinforcement in Concrete Bridge Deck Construction

The objective of this research was to document the occurrence of damage to epoxy-coated rebar after its installation on a bridge deck. The scope of work included visual inspection of the epoxy-coated rebar immediately prior to concrete placement, documentation of the types and locations of damage observed, and compilation of the damage types and frequencies for a bridge deck in northern Utah. The researchers recorded epoxy coating repairs, unrepaired end cuts, pliers strikes, and rib scrapes along portions of the longitudinal and transverse rebar, for a total of 363 m (1190 ft) of rebar. All of the observed 88 epoxy coating repairs were located at the ends of the bars, and only two unrepaired end cuts were observed. The number of pliers strikes along the longitudinal and transverse bars was 8 and 12, respectively. With 103 occurrences, rib scrapes were the most frequently observed type of damage; on average, 23 mm (0.92 in.) per lineal foot of rebar was observed to be damaged with rib scrapes in this study. In this severe environment, epoxy coating damage can lead to exposure of the reinforcing steel to chloride-based salts from wintertime bridge deicing operations, and the subsequent steel corrosion can affect the structural integrity and therefore the service life of concrete bridge decks. For these reasons, efforts to reduce the occurrence of damage to the epoxy coating on reinforcing steel are warranted.