Bridges epoxy-coated rebars

At present, epoxy-coated rebar is the most common corrosion protection system and is used in 48 states. At present, there are nearly 20,000 bridge decks using fusion-bonded epoxy-coated rebar as the preferred protection system. This amounts to nearly 95% of new deck construction since the early 1980s. 

The data from the Concrete Reinforcing Steel Institute (CRSI) shows that more than 3.6 billion kg (4 million tons) of epoxy-coated rebar (150 million m reinforced concrete) were used as of 1998. A significant amount of the epoxy-coated rebar was used in bridge decks. Over time, the formulation of epoxy has been modified to achieve better performance of the epoxy coating. 

Multiple Protection Systems Corrosion inhibitors are used in multiple corrosion protection systems in conjunction with epoxy-coated rebars and low-permeability concrete, in particular, for marine applications. Epoxy-coated seven-wire strands are not commonly used for prestressed concrete bridge members. Corrosion inhibitors are used in place of coated seven-wire strands in the prestressed highway construction industry. 

The protection system of choice on highway bridges in North America for a ressive chloride conditions continues to be fusion bonded epoxy coated reinforcement (FBECR). It was first installed in a bridge deck in Philadelphia in 1973 (Manning, 1996). It was estimated by the EHWA that 100 million sqnare feet (10 million m ) of bridge deck on the US federal-aid highway system contains epoxy coated rebar up to 1889 (Virmani and Clemena, 1998). 

Waterproofing membranes are routinely applied to new bridge decks in the UK and much of Europe, Several DOTs in the Northern USA and Canada also apply them. Membranes come as two main types, a liquid that solidifies in place, and a sheet that is stuck to the concrete (see Section 5,3,3), The main problem with waterproof membranes is similar to that of epoxy coating rebars they must be applied without defects. Defects can occur as blow holes, penetrations or mechanical damage to the liquid applied types, or cuts, tears, bad joins or perforations in the... 

Performeince of Epoxy-Coated Rebars in Bridge Deck FHWA-RD-96-092. 

Case No. 3 requires additional systematic testing, exhumation, and critical examination of existing structures involving dozens of bridge structures from different regions throughout the U.S. The structures, constructed with fusion bonded epoxy coated bar, must have been in service in high chloride environments for between 20 and 30 years. Part of the structure selection process has to include determination that chlorides have permeated to the rebar mat level at sufficient concentration levels to activate substantial corrosion if the structure were constructed from hare rebar. 

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