The closure was ordered when a serious crack was found in a load-bearing element of the 625.7m-long double-deck twin-arch bridge over the Ohio River.
Gary Panariello of consultant Thornton Tomasetti told a press briefing this week that crews have so far inspected about half of the 350 welds on the steel bridge that would normally carry the I-64 highway. Extensive non-destructive testing is being carried out to determine the extent of imperfections in the welds of the main tie. The entire structure is also being checked.
"The issues that create this particular problem are the presence of the high-strength fracture-critical steel that was used, the butt welds and the welding itself, the geometry and the fact that this is a tension tie," he said.
In parallel with the investigation, Thornton Tomasetti is working with the two states and the US Federal Highway Administration to develop solution options ranging from fixing individual cracks to replacement of the bridge. Panariello said that he expected the solution to be somewhere in between the two extremes.
