On April 5, construction workers will begin the next phase of repair on the four-lane bridge that carries I-80 across the Mississippi River between LeClaire, Iowa, and the Moline area in western Illinois.
The bridge is a key river crossing, carrying more than 30,000 vehicles per day.
Work on the 43-year-old bridge originally started last spring, with workers repairing its deck. During the course of that work, inspectors noticed corrosion in some of the structural components called floor beams whose cantilevered ends stick out from the side of the bridge and support the outside two lanes of the bridge deck. They also found a crack in one floor beam. So the Illinois Dept. of Transportation (IDOT) closed the bridge’s two outside lanes to prevent traffic from further damaging the bridge before it could be repaired.
John Wegmeyer, project implementation engineer for IDOT, explains that the damage is at expansion relief joints and affects only the cantilevered ends of the floor beams, not the center sections between the girders.
In November, Civil Constructors, of Moline and Freeport, Ill., submitted the lowest bid, $10.3 million, to repair the damaged end sections of floor beams, portions of eight stringers (small I-beams that lay perpendicularly across the tops of the floor beams), and to repave the associated sections of bridge deck.
Because the bridge is a vital link between Illinois and Iowa, the contract offers incentives totaling $1.4 million if the contractor meets or beats milestones that include getting two-way traffic flowing early before the summer travel season starts.
It also contains penalties of up $20,000 per day for missing milestones.
Although the section of bridge where the floor beams need to be repaired sits about 75 ft above the river, IDOT’s Wegmeyer and the contractor both say that the repairs can be made from the bridge itself, without using a barge-mounted crane in the river.