Cracked beam closes San Francisco transit center

SAN FRANCISCO (AP) — A second beam in San Francisco’s
celebrated new $2 billion transit terminal shows signs of cracking, an official
said Wednesday, a day after a crack in a nearby support beam shut down the
building that opened just last month.

The first crack found by workers installing roof tiles
Tuesday spans a beam holding up a park over the three-block-long Salesforce
Transit Center and runs over a downtown street, said Mark Zabaneh, executive director
of Transbay Joint Powers Authority, which operates the facility.

He said the problems were localized to that area of the
transit hub but it would remain closed “at least through the end of next
week” as inspections continued. It’s not yet clear what caused the cracks
at the facility that includes a bus deck, a towering sky-lit central entrance
hall and a rooftop park with an outdoor amphitheater.

“We’re working hard to rectify the situation,”
Zabeneh said. “We’re very disappointed with what happened; we will get to
the bottom of this.”

Mayor London Breed said the building would stay closed until
it was safe to reopen. Its role in the broader transportation system is too
important “not to act quickly to have definitive answers for the public,
and someone needs to be held accountable once the cause is determined,”
she said in a statement.

Engineers decided to shut down the station around 5 p.m.
Tuesday, as rush hour started, once they learned the extent of the cracking.

The transit hub, a commanding presence in the city’s South
of Market neighborhood where construction is booming, sits adjacent to the
so-called sinking condominium, Millennium Tower, which has settled about 18
inches since it opened over a former landfill in 2009.

Homeowners have filed multiple lawsuits against the
developer and the city, some alleging that construction of the transit center
caused the Millennium Tower to sink.

Zabaneh said he did not believe the cracked beams are
connected to ongoing problems at Millennium Tower.

Engineer Joe Maffei also said the troubles at the terminal
appear “completely unrelated” to the Millennium Tower’s sinking and
tilting. He said there have been no public reports of similar settling problems
with the terminal.

The first crack was found near a weld on a stress-bearing
horizontal beam and the second on a parallel beam, Zabaneh said. American steel
was used in the center’s construction, he said.

Construction experts say it’s exceedingly rare for steel
girders that support buildings to crack.

Engineer David Friedman said it’s likely the beams arrived
without cracks, but that once the weight of the roof garden and other
structures were added, “new stresses may have exacerbated the possible
fabrication flaws.”

The beams likely passed inspection after installation,
Maffei said.

“If that’s the case, it’s likely welding caused the
problem,” he said.

Buses were rerouted to a temporary transit center about two
blocks away that was used during the center’s construction. A downtown street
that runs under the beam also was ordered closed indefinitely, causing traffic
chaos at the same time some streets were closed for a conference sponsored by
Salesforce that was expected to draw 170,000 attendees.

Numerous towering condo buildings have gone up in the
booming South of Market neighborhood and several multistory construction
projects are underway. Officials voted in 2012 to scrap building-height
restrictions to encourage growth near the transit hub as San Francisco lures
technology companies from Silicon Valley.

Julianna Cheng, 32, who lives in the neighborhood, burst out
laughing when asked about cracking in the $2.2 billion transit center.

“I find it disappointing, but also kind of amusing
because they built this really big, they spent a lot of money,” she said. “I
feel like the money should have been used for a lot of other things.”

The online business software company Salesforce, which
opened its adjacent 61-story Salesforce Tower earlier this year, bought naming
rights to the transit center in 2017 as part of a 25-year, $110 million
sponsorship agreement.

 

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