Corrosion highway bridges

In the case of highway bridges, the vast majority of the problems are caused by chloride migration into the concrete because of deicing salt application and marine exposure. On reaching the surface, the chloride ions cause the disruption of the passive film and create conditions favorable for accelerated corrosive attack on the... 

One American estimate that there is 150 billion worth of corrosion damage on their interstate highway bridges due to deicing and sea salt induced corrosion. In a Transportation Research Board report on the costs of deicing (Transportation Research Board, 1991) the annual cost of bridge deck repairs were estimated to be 50-200 million, with substructures and other components requiring 100 million a year and a further 50-150 million a year on multi-storey car parks. 

In a more recent cost of corrosion study (Koch et al., 2002), the annual direct cost of corrosion on US highway bridges was estimated at 8.3 billion overall, with 4.0 billion of that on the capital cost and maintenance of reinforced concrete highway bridge decks and substructures. Indirect... 

Val V. D. et al. 1998. Effects of reinforcement corrosion on reliability of highway bridges. Engineering Structures. 1998. 

Chlorides are found as air pollutants mostly in maritime regions, where they are carried by wind-bome water droplets (aerosols). The salting of roads in winter represents another source of chloride that is of particular importance for the corrosion of vehicles and highway bridges. 

Figure 13.19 Corrosion ravaged columns of a highway bridge in Illinois. (Courtesy of Vector Corrosion Technologies)...

Figures show that corrosion costs the U.S. electric power industry as much as USS 10 billion dollars each year [8]. New studies on updating U.S. corrosion costs in 2000 have shown that the total cost of corrosion in 1999 dollars to remediate corrosion-induced structural deficiencies of highway bridges was estimated at approximately US 30 billion [9]. The same study showed that the current cost of corrosion protection built into new automobiles determined by auto manufacturers and other experts is US 150 per vehicle. In fact, the percentage of the GNP attributed to motor vehicle corrosion in 1998 was 0.25%. Other sources [10] report that BP had performed pigging on its Prudhoe bay pipelines more than 350 times in 2005. An example of the global ripple caused by this disaster was that when BP said that it would stop the flow of half as much oil in the summer of 2006, the price of oil increased by 3.4 percent, skyrocketing to US 77.30 a barrel the next day [11].

Y. P. Virmani, G. C. Clemena, Corrosion protection concrete bridge , US Department of Transportation, Federal Highways Administration, Report FHWA-RD-98-088, 1998. 

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