What are two common corrosion control measures for steel bridges?

• A. Protective coatings/paint systems and galvanizing or other sacrificial coatings
• B. Concrete overlays and epoxy floors
• C. Cathodic protection alone on all members
• D. Replacing steel with aluminum in all components

Answer: (A)

Corrosion control for steel bridges centers on keeping moisture and corrosive elements away from the steel and, when possible, giving the steel a sacrificial barrier. The two common measures are protective coatings or paint systems that create a continuous barrier to moisture, oxygen, and salts, and galvanizing or other sacrificial coatings that protect by corroding first, providing both a barrier and galvanic protection. Coatings must be properly applied and regularly maintained, with damaged areas repaired to keep the barrier effective. Galvanizing is widely used where harsh environments or high exposure make frequent coating maintenance impractical, and it can be coupled with additional coatings for added protection. Other options don’t address the steel members directly: concrete overlays and epoxy floors protect the deck rather than the structural steel, cathodic protection is used selectively rather than universally for all members, and replacing steel with aluminum isn’t a practical or common substitute in most bridges.