Cranes hoisted the final girder for the new SR-75 bridge at Lakeview into place Monday morning.
The girders – huge steel beams – will support the future bridge deck spanning Town Creek in DeKalb County, east of the Marshall County line.
Bigger and better
The $13.7 million bridge will be substantially longer, taller and wider than the old bridge built in 1942. Whereas the 82-year-old bridge is 280 feet long, 29 feet wide, and stands 54 feet above the creek, the new bridge will be 715 feet long, 38.5 feet wide and stand 75 feet above the creek.
The design corrects steep vertical curves on both bridge approaches.
Setting girders
During the last two months, contractors installed a total of 32 girders, individually weighing up to 44 tons. Cranes raised each girder into position. Then workers secured it to adjoining girders. Each splice required about 660 bolts.
Now begins the tedious, weekslong task of tightening roughly 23,000 bolts to a specified tension.
Following that, contractors will construct the bridge deck and rails and segments of roadway approaching the bridge, before demolishing the old bridge.
Few traffic impacts
Because the replacement bridge is being constructed on a new alignment parallel to the old bridge, the old bridge remains open to traffic during construction. Most work items should have little impact on traffic.
ALDOT anticipates completion of the project in about a year.
