The discovery of a cracked steel beam that forced the abrupt closure Tuesday of the brand-new Transbay Transit Center is the latest headache for the $2.2 billion transportation hub, which has been plagued by glitches and cost overruns since its inception. The cracked beam was spotted Tuesday morning by workers installing ceiling panels on the center’s third-floor bus platform, and concern over its potential failure prompted city officials to close the terminal and some streets at 4:30 p.m. They shunted rush-hour commuters to the nearby Temporary Transbay Terminal, which had been used during the center’s construction. The center sits next to the troubled Millennium Tower, which has sunk 18 inches since it opened in 2009. The damaged beam at the transit center was discovered on the same day that engineers inspected a cracked window on the tower, in an attempt to determine if it’s related to building’s sinking and tilting. The operator of the transit center was quick to give assurances that the two problems were unrelated. Now Playing: In the works for a decade, the new transit center combines muscular architecture with a lush varied park. Video: Carlos Avila Gonzalez “We don’t see a nexus,” Transbay Joint Powers Authority Executive Director Mark Zabaneh said at an afternoon news conference announcing the closure. The transit center is also adjacent to the recently opened Salesforce Tower, the city’s tallest high-rise. Salesforce, the cloud computing company and San Francisco’s largest employer, purchased the naming rights to both the transit center and its rooftop park. The call to close the transit center and Salesforce Park came on the same day that company founder Marc Benioff was celebrating his birthday and welcoming 170,000 conventioneers to his company’s annual weeklong Dreamforce conference. While the closure might not have shown those visitors the city in its best light, safety remained the top priority at the center, which opened just 45 days ago after 20 years of planning and almost a decade of construction. “The beam is cracked, so the behavior of the beam is unpredictable,” Zabaneh said. “We will be working tonight and tomorrow morning to get a better understanding of the cause of the crack.” The crack is in a 6½-foot-deep American-made steel beam on the third floor near Fremont Street. It’s one of dozens of beams that support the park above the bus deck and is topped by 5 or 6 feet of soil. Late Tuesday evening, the transit authority said it would inspect all steel beams in the center. The steel was fabricated by Herrick Corp. of Stockton under a $189 million contract with Skanska USA of New York, Transbay Joint Powers Authority documents show. In a statement released earlier in the day, Zabaneh said the crack appears to be a “localized issue and we have no information that suggests it is widespread.” But he added, “It is our duty to confirm this before we allow public access to the facility.” The transit center was designed by Pelli Clarke Pelli — the same firm that designed the adjoining Salesforce Tower — and was built by the joint venture of construction companies Webcor and Obayashi. “We are just beginning work and do not have any information about the cause or causes of the issue at this time,” Webcor said in a statement. All buses to and from the center were rerouted to the Temporary Transbay Terminal at Howard and Main streets, which was used for the past eight years while the new center was under construction. Fremont Street, one of the main morning commute arteries off of the Bay Bridge, was also ordered closed to vehicles and pedestrians between Howard and Mission streets, and was to remain closed until at least noon Wednesday. Officials encouraged motorists not to drive downtown. “Our advice for drivers, if it is at all possible, is to avoid that part of the downtown,” San Francisco Municipal Transportation Agency spokesman Paul Rose said. The cracked beam is the latest in a series of problems at the center. It was conceived 17 years ago as the “Grand Central Station of the West,” for buses, trains and high-speed rail — but rail service remains a distant hope, tied up in funding shortages, the uncertainty of California’s high-speed rail project and the logistical challenges of extending Caltrain tracks north from Mission Bay. Finances have long proved challenging. The center wound up costing $800 million more than expected and required a $260 million bailout from San Francisco to complete its construction. No sooner did the center open — an opening that was delayed by nine months — than the walkway that circles the nearly three-block-long rooftop park began crumbling. The shutdown is certain to put pressure on other transit options, but BART officials say they already are operating at full capacity, thanks largely to those 170,000 visitors attending Dreamforce at Moscone Center, where Howard Street is closed between Third and Fourth streets as part of the convention. “We are maxed out,” said BART spokeswoman Alicia Trost, noting that the district had 613 cars in service Tuesday, compared with the usual 595. The cracked beam is also reminiscent of the cracked bolts that plagued the eastern span of the Bay Bridge. “Big projects are increasingly complex,” said Randy Rentschler, spokesman for the Metropolitan Transportation Commission, which helped provide funding for both the bridge and the transit center. “No doubt a full investigation will be completed, and the engineers will get to the bottom of it.” San Francisco Mayor London Breed declined comment Tuesday, deferring instead to officials at the Transbay Joint Powers Authority. Supervisor Jane Kim, who sits on the authority and also represents the district at City Hall, said shutting down the building was “absolutely the right thing to do.” “We cannot put any of our residents or workers at risk,” she said. Supervisor Aaron Peskin, who has been critical of the project’s high costs, said he hoped the problem was a “one-off.” “They still owe us a quarter of a billion dollars,” Peskin said. “Happy Transit Week.” Chronicle staff writer Kurtis Alexander contributed to this story. San Francisco Chronicle columnists Phillip Matier and Andrew Ross appear Sundays, Mondays and Wednesdays. Matier can be seen on the KPIX TV morning and evening news. He can also be heard on KCBS radio Monday through Friday at 7:50 a.m. and 5:50 p.m. Got a tip? Call 415-777-8815, or email matierandross@sfchronicle.com. Twitter: @matierandross<doc-sep>SAN FRANCISCO — San Francisco officials shut down the city’s celebrated new $2.2 billion transit terminal Tuesday after discovering a crack in a support beam under the center’s public roof garden. Coined the “Grand Central of the West,” the Salesforce Transit Center opened in August near the heart of downtown after nearly a decade of construction. It was expected to accommodate 100,000 passengers each weekday, and up to 45 million people a year. The center is operated by the Transbay Joint Powers Authority and its executive director, Mark Zabaneh, said workers discovered the crack around 10 a.m. while replacing roofing tiles. Zabaneh said engineers spent the day inspecting the damage and decided to shut the station around 5 p.m., just as the afternoon rush hour started. “The beam is cracked,” Zabaneh said. “The behavior of the beam is unpredictable.” Zabaneh said the crack was found near a weld on a stress-bearing horizontal beam. He said he did not know how long the crack was, but he told reporters that American steel was used in the center’s construction. Zabaneh said the cause and the extent of the damage were unknown and the decision to close the terminal was made out of an “abundance of caution.” He said structural engineers would be working at the building Tuesday night to assess whether it is safe for people to return. 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 was also 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. Enveloped in wavy white sheets of metal veil, the five-level center includes a bus deck, a towering sky-lit central entrance hall and a rooftop park with an outdoor amphitheater. The San Francisco Chronicle reported that the complex faced delays in putting out contracts to bid, and the winning bids were ultimately higher than expected. The terminal’s cost rose from $1.6 billion at its 2010 groundbreaking to more than $2 billion in 2016 because of what one analyst called “optimistic assumptions,” according to the Chronicle. The project, a commanding presence in the city’s South of Market neighborhood, is financed by land sales, federal stimulus grants, district fees and taxes, bridge tolls, and federal and state funds. It sits adjacent to another dubious landmark, 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’s sinking. Zabaneh said he did not believe that the cracked beam was related to ongoing problems at Millennium Tower. The online business software company Salesforce, which opened its adjacent 61-story Salesforce Tower three months ago, bought naming rights to the center in 2017 as part of a 25-year, $110 million sponsorship agreement.<doc-sep>
SAN FRANCISCO – Even as they sought to assure the public that the cracked steel beam found Tuesday in the new Transbay Transit Center was an isolated incident, San Francisco officials acknowledged discovering a second compromised beam near the first one. The revelation added to the city’s embarrassment and increased concerns about the safety of a $2.2 billion transit hub that had to be closed a mere 45 days after its unveiling — and at a time when San Francisco is trying to display its finest wares. An estimated 170,000 visitors are in town for the yearly mega-convention hosted by cloud-computing giant Salesforce, whose name is attached to the transit center and the recently opened 1,070-foot building next to it. “The timing couldn’t have been worse,’’ said Josh Brown, who lives in the city and is attending the convention. “If you’re visiting and you’re like, ‘Let’s go check out the new Transbay terminal, the Salesforce area,’ Oh, sorry, you can’t. It’s going to collapse.’'" Beyond the poorly timed civic black eye, there’s the more serious matter of the safety implications of detecting faulty beams on the third floor of a structure built over more than three city blocks on seismically active terrain. Mark Zabaneh, executive director of the Transbay Joint Powers Authority, issued repeated assurances during a Wednesday news conference that the problem with the beams is limited to the east portion of the three-section facility, on the side over Fremont Street. Nonetheless, the hub will be closed at least until late next week while engineers work to develop a repair plan. “We will expand our investigation to make sure the transit center is sound and safe,’’ Zabaneh said. “We have no reason to believe at this point whatsoever that this situation exists anywhere but on Fremont Street.’’ The reasons for the defective beams – one with a crack across its full width of 2½ feet, the other one with less extensive damage – have yet to be determined, Zabaneh said. He mentioned issues of fabrication, welding, installation and design as possible culprits. Engineers plan to review the terminal’s design and determine whether those beams can support the roof and the public park above it. In the meantime, they will shore up the area of concern to relieve the load while seeking a permanent solution. “At this point in time, we don’t know what the cause of the crack is; we know the building is safe,’’ Zabaneh said. The transit center, envisioned as a “Grand Central Station of the West,’’ has been beset by complications that included an $800 million cost overrun and extensive construction delays. A month into its Aug. 12 opening, the half-mile walkway around the rooftop park started to crumble. In addition, the neighboring Millennium Tower has sunk 18 inches and tilted to the northwest since its debut in 2009, which its developers have blamed on groundwater pumping at the Transbay terminal’s construction site. Riders are now being diverted to the old Temporary Transbay Terminal a few blocks away. Waiting for a bus home to Oakland after his work shift at nearby BlackRock, Joseph Cobbina said he was “shocked’’ and “saddened’’ when he heard the new hub would shut down for a while. Sarah Larone, an auditor who works in Oakland, said the transit center’s problems don’t reflect well on her home city of San Francisco. “It’s just a shame that it’s new and it’s already falling apart,’’ Larone said. “I guess it happens, issues with buildings and windows and whatnot. At least the buses are still running. That would be upsetting if they didn’t.’’