CAMPBELL CO., Ky. — A major Tri-State interstate bridge remains safe to drive on, but more than a dozen steel repairs are necessary to keep it that way, transportation officials said.
Crews began work on the Combs-Hehl Bridge Monday night. The twin-span single-pier cantilever bridge carries Interstate 275 across the Ohio River, connecting Kentucky and Ohio. The Kentucky Transportation Cabinet owns and maintains the structure.
During a 2023 inspection, engineering firm Michael Baker International tested 300 welds and identified 16 locations that would need future repairs but posed no immediate safety issues, KYTC said.
Consultants and KYTC engineers collaborated to develop a repair plan that would prevent potential fractures and address these findings. The repairs will ensure the bridge can be safely traveled on for many years to come, KYTC said.
WATCH: Work is underway to repair steel after inspectors found 16 problem areas on the Combs-Hehl Bridge
The repairs follow a 2021 federal mandate ordering the inspection of older bridges across the country built with T-1 steel – a high-strength, quenched and treated steel known for being highly amenable to welding and machining. T-1 steel was developed in the 1950s and was commonly used in bridge construction until its discontinuation in the late 1960s.
The steel is highly susceptible to cracking due to hydrogen embrittlement, a reduction in the ductility of a metal as a result of absorbed hydrogen from poor welding. Potential issues had been found in other states with certain types of welds, which needed to be tested, KYTC said.
"The problems are with the welds that were made between the plates that make up these members. They were constructed before fracture control plans were required by the Federal Highway Administration (FHWA)," University of Cincinnati Associate Professor of Engineering James Swanson said.
We spoke with Swanson on Monday to get a better understanding of the structural issues associated with T-1 steel bridges.
The FHWA required the T-1 steel bridge inspections after a crack was discovered on the I-40 Hernando De Soto Bridge in Memphis, which connects Tennessee and Arkansas over the Mississippi River.
On May 11, 2021, bridge inspectors observed a partial fracture of a tie girder on the Hernando De Soto Bridge, an investigation report reads. The entire bridge was subsequently closed to traffic. A review of previous inspection records showed that a crack was present in 2019 and had extended between 2019 and 2021, fully fracturing the outboard side plate, top cover plate and the longitudinal fillet weld connecting the top plate to the inboard side plate.
A photo taken by a kayaker in 2016 appears to show a crack-like indication from afar at the same location, the report continued.
"If they were to construct (the Combs-Hehl) nowadays, they would find those in the fabrication shop before it ever went out to the field, and they would probably repair that much earlier before it became a problem and needed to be fixed in the field," Swanson said.
Work is now underway on the eastbound portion of the Combs-Hehl Bridge. Crews applied temporary striping late Sunday into early Monday to narrow lanes in preparation for the steel repair work.
Lanes will be reconfigured from three 12-foot lanes to two 10-foot lanes and one 11-foot lane. This setup will create room for barrier wall placement while minimizing impacts to traffic, KYTC said.
Additional lane closures may be required for crane operations and steel plate installation. KYTC will issue updates when those closures are scheduled. Eastbound work is expected to take about 45 days to complete.
When eastbound repairs are finished, crews will shift to the westbound side using the same traffic plan. More details will be provided closer to the start of that phase. Westbound work is also expected to take about 45 days, KYTC said.
In addition to the T-1 steel work, crews will also complete several stringer repairs. These repairs were added to the project to further enhance the long-term safety of the structure.
A queue warning system was installed on both sides of the river to alert motorists of slowed or stopped traffic on or near the bridge. The speed limit has been reduced to 55 mph through the work zone for the duration of the project.
"I drive across that bridge occasionally myself," Swanson said. "I don't have any worries."
KYTC said the priority is to minimize traffic delays during the project, even working with Riverbend Music Center to ensure no further closures on concert dates. KYTC said the goal is to complete repairs before the start of the Brent Spence Bridge Corridor Project, as many drivers are expected to use the Combs-Hehl as a detour.
M & M Services Inc. is contracted to perform the $2.2 million project on behalf of KYTC. Repairs are expected to finish by February 2026, weather permitting.
