Graves Co. students watch US 68 Eggners Ferry Bridge assembly | News
GRAVES COUNTY, KY (KFVS) - A group of about 20 students from Graves County High School visited the site where Hall Contracting is constructing a new span for the US 68/KY 80 Eggners Ferry Bridge.
Structural steel for the new span is being assembled at the Eddyville Riverport in Lyon County.
The students watched as steel workers assembled vertical supports for the new truss section and hoisted them in place with a crane.
Kentucky Transportation Cabinet District 1 Chief Engineer Jim LeFevre explained the process and answered detailed questions from members of three advanced math and engineering classes that joined forces for the field trip.
LeFevre explained that assembling the span on dry land, then taking it to the bridge on a barge to be lifted into place has helped to speed the construction process. The use of computer aided design also help to speed the process.
“We were able to get to the construction stage very quickly because of computer aided engineering," LaFevre said. "All of the holes drilled in the steel beams were guided by computers. That means when we get the beams here to the assembly point, everything fits more precisely, helping to simplify the construction work.”
Students were interested in how load calculations are figured to assure that the bridge is strong enough to carry loads that cross it.
“During the design process, we have several teams of engineers who review all of the calculations," he said. "In addition to factoring in the weight of the bridge, we calculate the maximum load that bridge will carry, then add a safety margin to assure it is safe for the driving public to cross.”
LeFevre said that while the new truss may look different to someone passing under the bridge in a boat, most motorists will probably not notice much difference, other than the new concrete on the deck driving surface.
After assembly of steel for the new truss span is complete, it will be lifted onto a barge to be transported to the Eggners Ferry Bridge site and placed on the existing piers.
The US 68/KY 80 Eggners Ferry Bridge has been closed since the evening of Jan. 26 when the 8,200 ton cargo ship Delta Mariner slammed into the bridge and knocked a 322 foot span into Kentucky Lake.
Hall Contracting has a $7 million contract to replace the missing span and get it open to traffic by Memorial Day weekend in time for the summer tourism season that is so critical to the economy in Kentucky’s Western Lakes Region.
According to the Kentucky Transportation Cabinet, the company hopes to have the new span assembled and ready to transport to the bridge site by sometime next week. They say once the replacement span is placed on the existing piers, the company will pour a concrete deck on the structure. The concrete will then have to cure several days before traffic can be fully restored.
Hall Contracting faces a $50,000 penalty for each day the company goes beyond the May 27 deadline for restoring traffic on the bridge. The Eggners Ferry Bridge normally carries about 2,600 vehicles across Kentucky Lake each day at the Marshall-Trigg County Line between Aurora and Cadiz..
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