The Fore River Bridge is located in Massachusetts and connects Quincy to Weymouth. The bridge has a center lift span to allow ships to travel underneath.
We were contracted by Canam, the fabricator of the lift span, to apply coatings. The lift span was made up of over 100 box girders. The box girders were delivered to our facility in Epping, NH. It was in Epping that all coatings were applied before the box members were transported to their place of assembly.
The MassDOT Bridge Painting specification requires that bridge members are sandblasted to an SSPC SP10. Box girders present a challenge because the interiors are not easily accessible. The areas are not only tight, but the interior includes diaphragms which present additional challenges of access.
Like many bridge projects, an organic zinc rich primer was used. Carboline was the chosen manufacturer and Carbozinc 859 was the coating. Coating members in such tight quarters can be difficult. However, working two shifts we were able to keep the flow of production rolling and prevent bare steel from becoming contaminated before the primer was applied.
Carboline Carboguard is a fantastic product and was the choice Midcoat. We stripe coated all the components before applying a full spray coat. After the spray coat was applied, it was important to remove all dry-spray through lightly sanding and with air.
The Top Coat was Carboline’s Carbothane 133. Just like the mid-coat, proper striping was important, even if the specification didn’t require it. After the coating was applied and allowed to cure for 48hours, we loaded the components on to our own trailers before delivering them to jobsite.