CONTACT Cable-stayed span over Mississippi River was connected without counterweights. |
(Photo courtesy of T. Y Lin)
The Route 74 Cape Girardeau crossing may be the last bridge in the U.S. to have its cables grouted, says Larry Owens, project manager for Evansville, Ind.-based Traylor Bros. Inc., the contractor. In recent years, sheathed cable-stays have become common. Since cable-grouting is not possible below 40°F, "hopefully the weather will cooperate and well get it all done by the end of the year," says Eric Krapf, project manager for the Missouri Dept. of Transportation.
The contract originally was awarded in 1996 to Flatiron Structures Co., Longmont, Col., but the contrctor negotiated out of the job when it encountered rock fissures that complicated foundation work, says Krapf. The state then hired Nicholson Construction Co., Puddy, Pa., to jet grout the fissures, "much like a dentist filling cavities," says Krapf.
Traylor Bros. rebid the job for $53.7 million and resumed work on two main piers, with goalpost-shaped 300-ft-high pylons and 50-ft-deep caissons that had to be blasted, says Owens. Flooding delayed work by five months and change orders may increase the contract up to $55 million, with some of that in litigation, says Owens.
Connecting the precast concrete-paneled, 100-ft-wide main span in August went efficiently, with step-by-step erection without special jacking or counterweights. Construction engineer T.Y. Lin International, San Francisco, constantly checked designer and contractor models against each other, says T.Y. Lin Senior Vice President Dave Goodyear. "On the second pylon, it was as efficient as could be," taking about a week, he says. Final connection came with less than an inch of tolerance.
Related roadwork in Missouri and Illinois is complete, and MDOT plans to let a demolition contract for the old 22-ft-wide bridge next year, says Krapf.ith the successful connection of a 1,150-ft-long cable-stayed main spans halves, a key crossing over the Mississippi River is set to open in December. The 4,000-ft-long Bill Emerson Memorial Bridge connecting Missouri and Illinois will be 75% wider than the existing 75-year-old former toll crossing and carry up to 26,000 vehicles daily.