NCHRP Synthesis 4, "Concrete Bridge Deck Durability," published in 1970, is still an excellent source of information on the nature of scaling and spalling and the causes of these mechanisms. However, engineers continue to search for methods of obtaining durable bridge decks, and the problem is becoming more urgent. It was reported in 1978 that nearly one-third of all highway bridge decks in the United States are seriously deteriorated due to corrosion of reinforceing steel. The cost of restoring these decks has been estimated at $6.3 billion. Virtually all protective systems currently in use to prevent corrosion of bridge deck reinforcing steel were developed following publication of Synthesis 4. In addition, methods of evaluation and rehabilitation have changed significantly since then. The current synthesis is, therefore, intended to supplement the earlier effort. This report of the Transportation Research Board reviews design and construction techniques currently in use to prevent deterioration of new bridge decks and also evaluation and rehabilitation techniques used to extend the service life of existing decks. Recommendations are included for research needs related to bridge deck durability. /Author/.
Samenvatting