Costly - but safest - Crosstown fix picked
Officials hope extensive repairs to the elevated lanes will restore confidence in the Tampa expressway.
By JEAN HELLER
Published January 28, 2005
TAMPA - State highway officials chose the safest and most expensive option Thursday in approving a plan to repair the elevated lanes of the Lee Roy Selmon Crosstown Expressway.
For bridge engineers, the decision finally defines the task ahead, requiring the strengthening of 165 of 218 support columns.
For commuters, it means that torn-up roads, construction delays and congested traffic could come to an end by the summer of 2006.
Still in question is who will pay the $75-million repair bill.
In addition to erring on the side of safety, officials hoped the more extensive repair program would restore public confidence in the $350-million toll road, which would be the region's largest albatross if no one felt comfortable enough to use it.
Commuters along the ground-level lanes of the Crosstown should see work stepping up there as early as next month as the schedules for installing the last of the support columns and repairing the flawed columns kick into high gear with an eye toward an opening in the middle of next year. Although the project belongs to the Tampa-Hillsborough Expressway Authority, not the Florida Department of Transportation, the state has a substantial investment in the road and has been overseeing the project all along.
After the collapse of one column last April led to the discovery of problems with others, Expressway Authority officials said they would comply with whatever repair strategy FDOT wanted.
The state faced two competing recommendations.
One, from Ardaman & Associates, a soils consultant hired by the Expressway Authority, recommended repair of 165 columns. The other, by URS Corp., the general engineering consultant on the project, said tests showed that fewer than 20 columns needed shoring up.
After an hourslong meeting in Tallahassee on Thursday involving state transportation officials, the Expressway Authority and engineers from several different firms, FDOT made its decision.
It came down "substantially" in favor of the report from Ardaman, which concluded that more than 75 percent of the underground support columns for the 6-mile reversible-lane highway need help, said Ralph Mervine, interim executive director of the Expressway Authority.
But Ardaman's latest estimates reduce by nearly half the number of columns that need the most expensive help. That rollback could cut the cost of repairs by about $5-million.
"I can confirm that FDOT concurred with the Ardaman conclusion and not with ours," said Tom Logan, regional vice president of URS.
Mervine said FDOT officials told him they were in "substantial agreement" with the Ardaman report, but had not completed documents supporting that decision.
In making their decision, FDOT officials appeared to ignore the results of highly publicized tests by a giant hydraulic hammer, which pounded on a select 12 support structures while engineers measured their abilities to withstand stress.
All 12 columns passed by the state-approved engineering standards applied to them when they were built, but 10 of the 12 failed when new, stricter state standards were applied.
The fact that more conservative standards were invoked at the mid-point in the project likely will be a key issue discussed when the parties involved go to mediation during the summer to determine who is at fault for the bridge problems and who will have to pay the $75-million repair bill.
It all began last April when one of the underground columns supporting an above-ground pillar sank suddenly 11 feet as the ground beneath it gave way. Problems were found with several more columns, and the entire project was shut down until all of the foundations could be subjected to more extensive testing to determine if they were in stable soil.
Most failed, in large measure because the soils under the Crosstown vary widely from limestone rock to clay to sand to muck, and a soil boring taken in one place didn't adequately reflect conditions a few inches away.
At first it was thought that most of the underground columns would have to be shored up by pinning them between two "sister shafts" and then tying the three shafts together under a cap that would spread the load from above over a wider area.
Ardaman said at first that of the 165 columns in need of repair, 105 would need the sister shaft treatment, which would cost from $215,000 to $425,000 per column. But two months after that November report, and after the results of the hammer tests, Ardaman said only 56 supports would need the sister shaft treatment.
[Last modified January 28, 2005, 05:06:36]
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