Selected Answers

From Tom Schwerdt of Active Transportation Advocates on May 14, 2014:
Prime all structural steel, including faying surfa ...read more Prime all structural steel, including faying surfaces with IOZ. Use A325 galvanized bolts. After installation, finish with your preferred midcoat and topcoat. In high-corrosion areas, consider stripe coating. Alternately, design the whole structure with weathering steel or ASTM A1010 as appropriate, with details such as drip tabs and/or bearing pans to prevent staining of the substructure.

From James Albertoni of CA Department of Water Resources on May 12, 2014:
A good approach would be to power-tool clean or bl ...read more A good approach would be to power-tool clean or blast the surfaces then use a sealant (compatible with the steel coating system) at the splice plate interface. Then apply a brush coat to the the interface and the the bolt heads. Then, lastly, apply the steel coating system over the entire splice plate assembly. All to often, though, we see the steel guys just slap some paint over it and call it good.

From Karen Fischer of Amstar of Western New York, Inc. on May 12, 2014:
On the vast majority of projects I've worked on th ...read more On the vast majority of projects I've worked on that require this type of work, the replacement steel is required to come to the jobsite primed (or will be cleaned to SP-6 minimum and primed in the field). The interface (existing steel onto which it will be placed) is generally remediated for salts, cleaned to a minimum SP-6, and primed with a zinc primer (as specified) with the necessary slip co-efficient. A caulking material is used beneath the plate that is compatible with the coating system and is applied to reduce water infiltration under the slice plate after installation. Then the entire repair area receives the remainder of a zinc/epoxy/Urethane coating system, including the bolt heads.