SAN FRANCISCO — The much-delayed and over-budget eastern span of the San Francisco-Oakland Bay Bridge will not open as scheduled on Labor Day weekend, transportation officials announced Monday, eliciting disappointment but little surprise in a region dependent on the soaring structure.
The Bay Area's second-most-famous visual icon was severely damaged in the 1989 Loma Prieta earthquake, killing a motorist and unleashing a generation of controversy.
The new span was scheduled to open in September with a splashy party costing more than $5 million and possibly including a bridge walk, a bike ride and a recreational run. But in March, it was discovered that 32 bolts on the structure had fractured.
The retrofit to fix that problem added an estimated $15 million to the $6.3-billion cost of the project, not to mention three months to its schedule.
On Monday morning in Sacramento, four Bay Area state senators were briefed on the project and the investigation into the construction defect. Sen. Mark DeSaulnier (D-Concord), co-chairman of the Legislative Bay Area Caucus, complained afterward that in 1998 he had been told the bridge project would cost $1.1 billion and be completed by 2003.
"It's frustrating, to say the least," DeSaulnier said. "We put the driving public at risk for much longer than we wanted. It's always been a race against time to get commuters off the existing eastern span of the Bay Bridge."
Last month, Gov. Jerry Brown signaled support for a delay, saying the span should not open until safety concerns were met. On Monday, spokesman Evan Westrup said: "We expect safety will continue to inform the Toll Bridge Program Oversight commission's decision regarding when the bridge will open."
Oakland Mayor Jean Quan said through a spokesman that she was still digesting the 102-page report on the investigation and would comment fully Wednesday during a public hearing in her city.
"We're disappointed that the new span will not be open in time for the Labor Day celebration," Quan said. "But safety has to remain our top priority. And we will be thorough and cautious as we adjust our plans."
The bridge is actually two separate structures of roughly equal length — a graceful suspension bridge to the west, connecting San Francisco to Yerba Buena Island in the middle of the bay, and a clunky cantilever number to the east, stretching from the island to Oakland.
Both were damaged in the magnitude 6.9 temblor, which struck during rush hour. The western span was retrofitted, but the eastern section was deemed too risky to keep. Construction on a replacement, which parallels the old one, began in 2002.
Bridge officials have said the new design includes "the world's longest self-anchored suspension span" — and that its price tag makes it "one of the largest public works projects in U.S. history."
When the new span was being built, the California Department of Transportation used large bolts that are common in the construction business, ones it had used in other bridges with no problems.
"But there were some distinct and significant differences in the Bay Bridge, and in retrospect, the report states, it was clear that a distinct and unique fastener should have been specified," said Randy Rentschler, director of legislation and public affairs at the Bay Area Toll Authority. "The question is, why wasn't it?"
The report said responsibility for the bolt failure was shared by Caltrans, bridge designer T.Y. Lin International/Moffatt & Nichol Joint Venture and builder American Bridge/Fluor. The enormous bolts failed because of a phenomenon called hydrogen embrittlement, in which hydrogen atoms invade the spaces between the steel's crystalline structure and weaken it.
In all, 96 bolts will be replaced before the bridge opens, including the 32 that broke during testing. An additional 192 will be replaced after the bridge opens, Rentschler said, adding that more may be switched out over time.
The bolts will be replaced with so-called saddles, which could take until about Dec. 10 to create and install, Rentschler said. "Until the work is done, traffic will not move onto the new structure," he said.
Once the structural work is completed, transportation officials will need to close the bridge, which carries 280,000 vehicles daily, for four days to repave lanes and reroute traffic onto the span.
"We are very sorry for this delay," said Steve Heminger, executive director of the Bay Area Toll Authority. "But we have a retrofit that we need to get built, and we need to get it installed, and we need to do it right."
maria.laganga@latimes.com
patrick.mcgreevy@latimes.com
La Ganga reported from San Francisco and McGreevy from Sacramento.
Anda sedang membaca artikel tentang
Bay Bridge eastern span opening delayed by safety concerns
Dengan url
http://penyakitberbahayakan.blogspot.com/2013/07/bay-bridge-eastern-span-opening-delayed.html
Anda boleh menyebar luaskannya atau mengcopy paste-nya
Bay Bridge eastern span opening delayed by safety concerns
namun jangan lupa untuk meletakkan link
Bay Bridge eastern span opening delayed by safety concerns
sebagai sumbernya
0 komentar:
Posting Komentar