State officials said Friday that finding the cause of support column cracking in the reworked interchange of Causeway Boulevard and Interstate 10 is proving to be a vexing task. The Times-Picayune archiveSouthbound Causeway traffic merges between Veterans Boulevard and Interstate 10 in September. The interchange is a sea of detour signs, barrels and construction. "Realistically, we really don't know...
State officials said Friday that finding the cause of support column cracking in the reworked interchange of Causeway Boulevard and Interstate 10 is proving to be a vexing task.
Southbound Causeway traffic merges between Veterans Boulevard and Interstate 10 in September. The interchange is a sea of detour signs, barrels and construction."Realistically, we really don't know what's going on with the concrete," said Bambi Hall, spokeswoman for the Department of Transportation and Development, in a news conference.
Hall and other transportation officials said the cracking is extremely rare.
"We're in uncharted territory," she said.
Cracks in a support column and cap prompted the department last week to close a new ramp connecting northbound Causeway to westbound I-10 as a safety precaution.
"We will not hesitate to close any ramp, any bridge, any road that has a potential safety issue," said Michael Stack, district administrator for the Transportation Department.
Crews removed a similarly cracked column and cap on Nov. 5 in a location where a ramp from southbound Causeway to eastbound I-10 has yet to be built atop the columns.
Both damaged columns were erected in 2006. Even since then, Stack said, road building technology has improved, and officials could decide to apply new techniques that were not available in 2006 as they restore the columns.
Department engineer Frank Standige said investigators will analyze samples of the cracked concrete to identify its weaknesses.
"It's a very tight crack," Standige said. "You wouldn't notice it, probably, if you passed by."
But the crack kept spreading after inspectors started monitoring it in recent months, triggering the concerns.
Stack said temporary supports could allow the ramp to reopen in weeks as the investigation and permanent repairs proceed. He said the column is not in danger of collapse.
The cost and duration of the repairs remain unknown. The work could range from filling the cracks in the existing column and cap to replacing the concrete forms entirely.
Boh Bros. Construction built the forms and is working with the Transportation Department on the fixes. Stack said it is unclear whether the problem grew from the company's earlier work, originated with the particular mixture of concrete the department approved or stemmed from some other cause.
The officials suggested that drivers moving north on Causeway who want to travel west on the interstate take the southern interstate service road east to Bonnabel Boulevard and make a U-turn. Or they could cross to the northern side of I-10 on Causeway and move over to the temporary westbound exit at Severn Avenue.
If there is any consolation for drivers grappling with traffic at the busy, construction-plagued intersection, officials said, it is that the northbound to westbound ramp carries the lowest traffic load and has the smallest impact on Lakeside Shopping Center and surrounding shopping in Metairie.
The $35.6 million first phase of the Causeway and I-10 interchange upgrade is still on track to finish in spring 2011 despite this late challenge, officials said, with all the ramps on the eastern side of the interchange opening by Jan. 1.
The $51 million second phase, covering ramps on the western side of the interchange, will remain under construction until 2012.
Then transportation officials will shift their longstanding I-10 expansion campaign to widening the interstate and adding sound walls from Clearview Parkway to Veterans Memorial Boulevard.
Mark Waller can be reached at 504.883.7056 or mwaller@timespicayune.com.