Repairs planned for U.S. 90 cracks
By JEAN L. KAESS
The project to repair girder cracks on the elevated section of U.S. 90 over Bayou Ramos will be let for bid in October.
Phase 1 of the Bayou Ramos rehabilitation includes repairing girders and load testing.
“By conducting the load testing we will be able to determine if we can modify the weight restrictions currently in place,” said Deidra Lockhart, public information officer for the state Department of Transportation and Development District 3.
Previously, DOTD officials said remaining girders will be addressed in Phase 2, which is scheduled to take place in fiscal year 2013-14.
In June, engineers determined that the concrete used to pour the affected sections was good.
Core samples from the damaged sections revealed no irregularities, according to state DOTD District 3 Engineer Administrator Bill Olivier.
“We still are not sure of what the causes are,” Olivier said, adding that engineers may never know the reason unless the girders — located between the substructure where they hold up the decks cars drive on — are destroyed and studied.
Olivier called the cracks “unexpected” in a bridge of this age. It opened July 20, 1999, but this particular section was constructed in 1994. He noted that the problem is unique in the state, but may not be unique in the nation.
Because he has not seen the cracks himself, Olivier could not describe the amount or size of the cracks, but said they are “a little more than hairline.”
The cracks were discovered while the DOTD was conducting a routine inspection in March. The bridge’s load limit was reduced shortly thereafter with truck traffic weighing greater than 15-25 tons being detoured to guarantee that no further damage will occur to the structure.
That weight limit, as well as the detour for trucks over the weight limit, remains in effect until the bridge section is repaired.
The detour for trucks traveling westbound is U.S. 90 to Lake Palourde Bypass Road (exit 181) to La. 182 and back to U.S. 90. The detour for trucks traveling eastbound is U.S. 90 to La. 182 (Morgan City exit) to Lake Palourde Bypass Road and back to U.S. 90.