Photo shows cut steel strands
TDOT officials said Tuesday they believe that an oversize load caused a frightening bridge collapse at the busy intersection of I-24 and I-75.
One person was injured when a beam fell shortly before noon on Monday. Hospital officials said that person was in critical condition. TDOT officials said that driver apparently ran into the beam after it fell.
The incident caused a massive traffic backup. TDOT was able to get one lane open on Monday night.
TDOT is drawing up plans to get a side barrier again on the bridge and be able to open it for two lanes. The lanes will be narrower than they were before because the collapsed beam is not being replaced.
TDOT Chief Engineer Paul Degges said an examination of the collapsed beam showed that five different steel strands had been cut in the same area of each strand.
He said, "It was like somebody ran a pair of scissors through there."
The beam has 23 3/8 inch steel strands in all.
Mr. Degges said the collision with the bridge may have happened shortly before the fall, or it could have been as much as three days earlier. He said it was likely the top of whatever struck the bridge was made of steel.
He said TDOT cameras in that intersection are for traffic monitoring and not for investigative purposes. He said the cameras do not record.
Mr. Degges said TDOT has been working with the Tennessee Highway Patrol to try to find which operator may have struck the bridge, but has not yet had any success. "No one has come forward with any video," he said.
He said the THP checked arrivals at its Manchester truck weigh station for that morning without finding a possible culprit. However he said the collision may have come prior to Monday. The TDOT official said he expects the cost of the damage to the agency to be around $300,000.
He said that bridge, which dates to 1959, is slated to be torn down within 18 months as a major reconfiguration of that intersection takes place. He said vehicles are not allowed to carry equipment that rises above 16 1/2 feet without a special permit.
Mr. Degges said several bridges are hit each year in Tennessee and sometimes substantially damaged. He said often the offenders are caught and their insurers end up paying for the damage.
Paul Degges