Ohio Bridge's Big Girders Galvanized for Corrosion Protection

Stark County OHIO

For the past three decades engineers working for Stark County, OH have recommended the use of hot dip galvanizing to protect new and retrofitted bridges. Recently they really went the distance, specifying galvanizing for bridge girders that stretched the capacity of the local galvanizing company.

Because of the length of the bridge county personnel were concerned that hot dip galvanizing might not be possible. After meetings involving the design consultants, county engineers and the galvanizer, it was decided that three 80-ft girder sections met the design criteria for the bridge and could in fact be treated by the double-dipping process. This is a two-step procedure that allows pieces that are longer or deeper than the bath to be galvanized by dipping each end sequentially and independently so that the entire item can be coated.

In this case 80-ft plate girders were welded together with connector plates that averaged nearly 4.5 feet deep. Girders weighed from just under 17,000 pounds to nearly 27,000,650 pounds.

Cost wise it was determined that hot dip galvanizing the Blough Avenue Bridge was the most economical method of corrosion protection. At $2.85 per square foot, the initial cost of this method was less expensive than the Ohio Department of Transportation's paint system. Over the life of the bridge, the cost of galvanizing is anticipated to become still more attractive. It is expected that the galvanized surface will resist corrosion and remain maintenance-free for at least 50 years.