Section 4: Bridge Deck Protection SystemsAnchor: #i1001447
Protection with Linseed Oil
The department's practice is to seal bridge decks with linseed oil. For decks, treatments with linseed oil—or an equivalent or better material—after the bridge is in service is advisable if it is exposed to coastal saltwater and/or deicing salt. This treatment is also recommended if cracking is exhibited after construction and it is necessary to prevent water from contracting the reinforcing steel. Such treatments are also advised in areas where significant scaling damage associated with freeze-thaw cycling has been noted. Linseed oil should be reapplied every three to five years to maintain the protection system.Anchor: #i1001458
Protection with Silane
Penetrating concrete surface treatments such as silane are gaining in popularity as an alternative to linseed oil. The use and application is very similar to linseed oil, but the reapplication frequency is seven to ten years. Proper cleaning is required to achieve the desired penetration of the silane. Bridges initially treated with linseed oil should not be treated with silane.Anchor: #i1001468
Asphaltic Protection Systems
The Texas Bridge Deck Protection System, consisting of a two-course surface treatment followed by an asphalt overlay, is no longer considered to be an adequate protection system. Its use is discouraged, especially for districts where decks are exposed to coastal seawater or deicing chemicals. Microsurfacing consisting of a thin layer of polmer modified asphalt with an aggregate and mineral filler also is not considered to be a bridge deck protection system.
For bridge decks which are already under distress, it may be possible to extend their life by applying the two-course surface treatment with an overlay, but this should be considered temporary until the deck can be repaired or replaced. If the decision is made to apply an asphalt overlay, a two course surface treatment must be applied prior to the overlay.