TDOT to do emergency repairs to I-81 bridges

Cracks in beams formed since July 2008 inspection of Greene County bridges

November 10, 2009

The Tennessee Department of Transportation (TDOT) will perform emergency bridge beam repairs to the I-81 northbound and southbound bridges over U.S. Highway 11E at exit 23 in Greene County over the next two weekends. TDOT crews will close the I-81 northbound bridge on Saturday, Nov. 14 at 10 p.m. ET to begin repairs and will reopen I-81 north by 10 a.m. ET on Sunday, Nov. 15. TDOT crews will make repairs to the I-81 southbound bridge the following weekend beginning at 10 p.m. ET on Saturday, Nov. 21 until 10 a.m. on Sunday, Nov. 22. During each closure, traffic will be diverted down the off-ramp at exit 23, across U.S. 11E and back onto I-81.

Three cracks, two in a bridge beam on the northbound bridge and one in a beam on the southbound bridge, were discovered by a work crew involved in the ongoing $1.2 million rehabilitation project that includes bridge deck repairs, painting and the installation of an over-height detection system on U.S. 11E to keep trucks with large loads from hitting the bridges.

“Unfortunately this emergency repair is occurring at the same time as the I-40 rock slide in North Carolina, but the safety of the traveling public is our number one priority,” said TDOT Chief Engineer Paul Degges. “We’ve scheduled the repairs at night so they have the least impact on motorists. The bridges are safe for travel, and we’ve been keeping a close watch on them since the cracks were discovered. Still, the repairs need to be done sooner rather than later.”

TDOT believes the cracks developed sometime after the last bridge inspection was conducted in July 2008. The cracks were discovered by a construction crew performing repairs on the bridge. TDOT personnel were alerted and the repairs were immediately scheduled.

The cost of the repairs, estimated at $79,271, will be added to the existing bridge rehabilitation contract being performed by General Constructors Inc. from Mount Juliet, Tenn. Crews will use a welding technique called full-penetrating welding where molten metal is created during the process and penetrates through the entire bridge beam and eliminates the cracks. Before traffic is permitted to cross the bridge, TDOT will inspect the weld using X-ray technology to ensure the weld was performed correctly.

TDOT has been in close contact with the North Carolina Department of Transportation about the repair project. TDOT and NCDOT will not alter the I-40 detour during the repairs.