The steel “belly” girders have begun to arrive at the Highway 47 over the Missouri River bridge construction site.
The girders, which arrived by barge, were fabricated in Indiana and make up the bulk of the 3 million pounds of reinforcing steel being used in construction of the bridge.
According to Missouri Department of Transportation Area Engineer Judy Wagner, the completed bridge will have 11 girders, including five sets of steel and six sets of concrete girders. The girders vary in heights from 10 to 16 feet and span up to 500 feet across the river
The barges carrying the girders traveled on the Illinois River to the Mississippi River near Grafton, Ill.
“We are hoping to get them all stored there so they are below the (geographic) ice line,” Wagner said.
Once on the Mississippi River, the girders are barged by Hermann Sand & Gravel, Inc. to Washington. More are expected to be delivered over the next few weeks, Wagner added.
The goal still is to have all of the work conducted in the river completed by spring, according to Wagner. Maintaining that schedule is important to complete the bridge by December 2018.
“That is critical,” she said. “By the end of the year we want everything in the substructure to be poured. We are still on schedule to do that.”
She noted that flooding always is a concern for bridge work during rainy seasons, and historic high waters earlier this year already delayed the $63 million bridge project. The bridge contractor, Alberici Constructors Inc., was delayed weeks due to flooding after nearly 11 inches of rain fell between April 26 and May 5.
Work had been slated to end Nov. 1, 2018, but the revised completion date is mid-December. In June, Alberici requested additional time to complete the project due to setbacks during flooding.
When the Highway 47 bridge over the Missouri River is complete, there will be 11,900 cubic yards of concrete used in its construction. There will be 4,500 cubic yards of concrete on the driving surface and 7,400 cubic yards on the rest of the bridge.
The project includes 15 drilled shafts supporting the 2,560-foot-long bridge. Each 10-foot diameter drilled shaft is 60 to 75 feet long and embedded into bedrock up to 20 feet.
The bridge will have two 12-foot driving lanes with 10-foot shoulders.
Along the bridge there will be 587 light fixtures and 15,954 LED lights.
There are an average of 50 to 60 workers on the bridge during construction hours.
That number will increase to up to 200 after the bridge deck is poured and carpenters, ironworkers and others will be at the site at the same time.
According to Wagner, one attribute that differs from other bridges is the biking and pedestrian path on the west side of the bridge. The path is 10 feet wide, compared to most bridge pedestrian paths that are 8 feet wide.
Along the path is a vista, an overlook where walkers and bikers can stop and view the river and cityscape. It will be located at the center bridge pier.
Alberici crews began work on the project in August 2016 after the Missouri Highways and Transportation Commission awarded the contract.
The bridge is being constructed upstream from the existing span, which was completed in 1936.