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Mounting costs, controversy about outsourcing to China, and long delays have dogged the construction of the East Span of the San Francisco-Oakland Bridge
When it is finally completed in 2013, the new East Span of the San Francisco-Oakland Bay Bridge will be the most expensive bridge of all time. It will also go down as one of the most controversial construction projects in American history. In its short, but rich history, the East Span project has inspired angry debate about rising costs, long delays, outsourcing to China and its ability to withstand earthquakes. To add to this rich brew, in November 2011, an East Span safety inspector was sacked for faking his test results.
The delays and rising costs are, of course, intimately linked. The bridge was supposed to be completed in 2007, but the opening has been put back to 2013. Back in 2005, the East Span was going to cost $2.6 billion, but the New York Times says the figure now stands at $7.2 billion, a sum not disputed by the California Department of Transportation (Caltrans), which is responsible for the bridge.
Yet, outsourcing a lot of the East Span’s steelmaking to the Chinese company, Zhenhua Port Machinery Co. (ZPMC), was supposed to make it cheaper and get the job done more quickly. As Brian Raff, the National Steel Bridge Alliance Marketing Director said: “The reason American fabricators couldn’t perform the work had nothing to do with US fabrication capabilities, but with scheduling issues. As it turned out, the Chinese fabricators could not meet the schedule either. The first delivery of Chinese steel was 15 months behind schedule and the project is years late.”
Criticism has also been directed at the bridge’s signature element, a 2047-foot-long self-anchored suspension segment, which necessitated a 525-foot tower. No one disputes its beauty, but it has drawn criticism over its structural viability in a seismic zone.
Made in China
Although fabrication is taking place in seven foreign countries and two dozen American cities, China is by far the biggest contributor of manpower and machinery. Shanghai’s ZPMC won the sub-contract for the steelmaking on the SAS sections, as well as the decks and tower legs.
ZPMC did not win the bid directly with Caltrans. Its steelmaking capacity formed a critical part of the bid put together by American Bridge/Fluor (ABF) to do the work on the SAS tower. Chinese steel and labour, according to Caltrans, made the work $400 million cheaper than domestic steel fabrication.
Caltrans claimed the American steel industry lacked the capacity to build such massive steel structures on schedule, whereas ZPMC could get the job done quickly. The argument goes that the saving of an estimated $400 million was a mere side benefit.
But the United Steelworkers Union’s legislative counsel, Linda Andros, said the US steel industry could have done the work on time had it been given the opportunity. She claimed an American joint venture (JV) bid on the unique bridge sections and was pre-approved by Caltrans.
“In 2006, ZPMC had no capacity to produce these unique bridge sections but after winning, they built capacity. That’s precisely what the US JV was prepared to do,” she said. “Not only did the US steel industry lose hundreds of jobs, but also the Chinese Government now has the technology, jobs, revenue and capacity. So, if somebody else builds a unique bridge we’ve created a strong competitor. That’s why it was a penny-wise and pound-foolish decision.”
This is where the two sides of the debate disagree profoundly. Caltrans’ publicity officer Bart Ney flatly contradicts Andros. He says there never was an American JV. “There was talk of one. Oregon Iron Works was to be part of it and ended up doing great work on our bridge, but at the end of the day no American companies came together in a JV to bid, or even negotiate,” he said.
Ney explains that it is a widespread misconception that the steelmaking was put out for a bid. “It did not go out to bid because it was a subcontract to our prime ABF Joint Venture. So the Chinese did not win the ‘bid’. ABF chose ZPMC because they had the capacity and chose to create additional capacity swiftly so they could isolate and focus on our project.”
Ney concluded: “The US has a talented and technically sophisticated steel industry, but currently lacks the capacity for this type of large steel component construction.”
But Ney’s argument that the American steel industry could not have produced the structures on time loses force when one considers the struggles of ZPMC’s steelworkers to meet the technical challenges, and the long delays.
There is little doubt that ZPMC’s facilities are first-class. Its manufacturing base sprawls more than two square miles along the southern shore of Changxing Island, in the mouth of the Yangtze River. The fabrication yards for the Bay Bridge project are within the warehouses where 20,000 people work, forging 80 per cent of the world’s container cranes.
But it is no secret that there was an epidemic of quality-control incidents in the early days of the project. ZPMC is a specialist in building harbour cranes – it provides 75% of the world’s supply. Inevitably, its welders were not as skilled at bridge-building.
William Ibbs, a professor of engineering at the University of California, Berkeley and a designer himself, said all the quality control issues in Shanghai had slowed down shipments to the US, and inflated costs.
“San Francisco would receive the pieces from China and slot them into place like pieces of a jigsaw puzzle,” he said. “They put piece A up, then piece B goes next to it, then piece C. But there were many instances when the quality control of the welding work in China scrambled the delivery sequences of the sections to the US. Piece A was barged to the US, but then welds failed the tests and it was set aside. Then C was fabricated and shipped to the US. So, then we get C sitting idly on a barge in the bay while waiting for B to be fixed and shipped,” he said.
Ibbs said the delays meant Caltrans’ estimate of $350 million for the ZPMC work – a saving of $400 million – is not accurate. “The costs were higher than expected because if you lose a week when piece B is not there on time, you have to pay standby costs, and the contractor is not able to use ironworkers as productively. I do think the outsourcing saved money, but less than has been claimed. Instead of 1 dollar, they’ve saved 67 cents, about two thirds,” he said.
To improve ZPMC’s standards, both ABF and Caltrans sent out engineers to supervise the work. At one time, there were 300 inspectors based in Shanghai. Caltrans also introduced an expensive quality control system which involved placing green tags on every component. Gradually, over time, the welding quality improved, but at a high cost.
Li Jianghua, ZPMC’s general director of this project, described how the relationship between the Chinese and Americans developed. He said at first ZPMC “was a kid who was learning to walk in the industry of bridge building”.
“We regarded our American friends as our teachers and studied a lot from them. We were below them at that time. With smooth progress of this project and accumulation of experience, we could stand on the same line. But now, with the steel structure fabrication completed successfully and many standards surpassed, the American side become admiring and looking up to us. Our technicians have won the respect of the clients depending on their sweat and wisdom,” he said.
The bridge’s history
The need for a new East Bay bridge was evident after October 17, 1989, when the old 1936 bridge was damaged in the 6.9 magnitude Loma Prieta earthquake. A 50-foot section of the upper deck collapsed, indirectly causing one death and the East Span was closed for just over a month.
It was obvious a major earthquake on either of the two local faults – the San Andreas and the even more dangerous Hayward – would destroy the major cantilever span. The eight-mile-long Bay Bridge is actually two separate bridges, separated by Yerba Buena Island in the middle of San Francisco Bay. The West Span Bridge, between San Francisco and Yerba Buena Island, has already undergone extensive seismic retrofitting.
At first, the state authorities planned a similar $200 million refit to the 2.2-mile long East Span, which runs from Yerba Buena Island to Oakland. But in 1996 two Caltrans panels advised that a simple replacement bridge would cost just a few hundred million dollars more than a refit. The new plan was to build a simple elevated viaduct of reinforced concrete columns.
But the public felt the design was too ugly to sit alongside the beautiful West Span. And after much debate, a Caltrans Panel in 1998 recommended incorporating an SAS tower into the East Span, at an estimated cost of $1.5 billion. Later that year, the state authorities held a design contest.
Work finally began in 2002, with an initial completion date of 2007, which Caltrans put back to 2009 a few months later. But the rising costs became an issue and on December 10, 2004, Governor Arnold Schwarzenegger scrapped plans for the SAS bridge. He announced that the original design of a simple viaduct would be built after all. Debate raged for six months, then Schwarzenegger changed his mind again and resurrected plans for the SAS span. The new date for completion was 2013 and bridge tolls were raised to cover the extra billions.
New bids for the main span were opened on March 22, 2006, which ABF won with a low bid of $1.43 billion. Their costs included outsourcing to China to save money.
Controversy has dogged the project throughout. But the most serious allegations came recently, in November, 2011, following an investigation by the Sacramento Bee newspaper. As a result of the expose of problems involving faked tests on the Bay Bridge, as well as other freeway structures in California, Caltrans sacked Duane Wiles, who tested foundations, and his supervisor, Brian Liebich, chief of Caltrans’ Foundation Testing Branch. Caltrans’ officials insisted the Bay Bridge was safe, but have not yet released documents to prove their assertions. There is an ongoing FBI investigation into Wiles’ work.
Technical challenges
ABF’s greatest engineering challenge was posed by the bridge’s signature element, the 2047-feet long suspension segment, with its 525-foot tower, which is slightly higher than the tallest towers of the West Span. Because the East Span is self-anchored, it is not fixed to landfalls. The middle of the main cable is threaded underneath the western side of the East Span, with the two ends draped across the top of the tower before descending to the eastern side, where they are anchored in the concrete decks.
Some engineers have claimed it will be vulnerable to earthquakes. The most influential critic has been Abolhassan Astaneh-Asl, a Professor of Structural Engineering at the University of California, Berkeley. He told the San Francisco Chronicle: “Single-tower suspension bridges are inherently unstable and become even more unstable when they are self-supporting like the East Span Bridge. The main cable is connected to the deck, not the ground. It’s like anchoring a ship to itself, not to the sea bottom. The whole roadway is under such tremendous compression that any extra stress, like a quake or explosive charge, could make it collapse completely.”
However, Professor Astaneh-Asl’s view was rejected by Prof Frieder Seible, who as chair of the Caltrans Seismic Advisory Board, tested its resistance to earthquakes.
Prof Seible tested the East Span’s structures, including the 525-foot tower, at UCSD’s state-of-the-art research laboratories. These boast the world’s only outdoor shake table, which has a 2,000-tonne payload, allowing full-scale testing. “For the East Span we needed all our capacity to get the correct damage patterns and failure modes to measure earthquake performance,” he said. “We tested the components mainly at full-scale, and the smallest scale for this bridge was one in four.”
He said the results were incontrovertible: “We showed in every case that all the components where you might expect inner-lasting damage were resistant to at least double the capacity required.”
Whether or not the bridge is worth the extra billions of dollars is a matter of opinion, says Prof Seible. But Ney believes the project will be worth it when it finally opens in September, 2013. “The iconic part of the new east span is the SAS. The Skyway, Oakland Touchdown (OTD) and Yerba Buena Island transition (YBI) take their architectural cues from the SAS,” Ney said. “Just innovating what was needed seismically took years to achieve and build. Since we had to spend the time and money anyway, the region and the state opted to build an iconic structure with a life span of 150 years, which is double the life span of a traditional new bridge.”
David W. Smith
A longer version of this article appeared in Construction Research & Innovation, Vol 2, Issue 4, December 2011. Visit http://www.constructionbooksdirect.com/CRI/