Posts tagged with "San Francisco":

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CMG to bring back 1912 feel for San Francisco Civic Center overhaul

After over a year of community review, a refined vision plan by CMG Landscape Architecture designed to upgrade and modernize San Francisco’s Civic Center district is moving forward. Backed by a supergroup design team that includes Kennerly Architecture + Planning, Gehl Studio, HR&A, and others, CMG’s proposal seeks to retool the multi-block plaza and pedestrian mall to better fulfill the original 1912 Beaux Arts plan proposed for the site by architect John Galen Howard, designer of the University of California, Berkeley. CMG’s vision is part of a larger effort spearheaded by the City of San Francisco called the Civic Center Public Realm Plan, a scheme that seeks to articulate a “unified vision for long-term improvements to the area’s public spaces and streets.” As it stands, the Civic Center area is anchored by three major public spaces that are each being reworked by the latest plan to promote universal accessibility, access to nature, and around-the-clock public use. CMG proposes to transform the namesake Civic Center Plaza flanking City Hall into a series of outdoor “garden rooms” that surround a central square. The four garden rooms will contain a pair of lawns and newly planted tree areas that celebrate and frame a pair of recently refurbished playgrounds. The space will be anchored by an interactive play fountain that can be turned off during the protests and gatherings that take over the space. On the opposite end of the axis that runs through the district, the United Nations Plaza will see significant changes, including the “adaptation” of an arresting but unloved Lawrence Halprin–designed monumental fountain. The connecting block along Fulton Street that links the two plaza areas will be upgraded as well, with new soccer fields installed in the space between the Asian Art Museum—where wHY is currently planning an ambitious expansion—and the San Francisco Public Library buildings. Willett Moss, founding partner at CMG, said, “Initially we thought the plan would be responsive to the district’s diverse demographics with a multitude of culturally specific amenities and experiences. However, through the process, we realized that the vast majority of people want essentially the same thing—a space that’s inclusive, accessible, and celebratory.” A final version of the community-led design will be unveiled later this year with final completion of the project expected by 2022.

San Francisco Design Week 2019

SAN FRANCISCO DESIGN WEEK kicks off June 20 – 28 at the Design Hub at Pier 27, celebrating with the theme CommUNITY. Join the Opening Night Reception followed by a day of exclusive programming at the Hub. Experience interactive exhibits, product displays, installations and talks, including the 2019 Design Awards and CommUNITY Art Silent Auction. All week hosted events are held across the region at design studios, museums, restaurants, shops and pop-up venues. Highlights include hosted talks and workshops by design leaders such as Yves Behars’ fuseproject, a rare visit to Ken Fulk’s studio and St. Joseph’s Art Society, and Swiss designer Adrien Rovero’s show-stopping art installation.
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Beleaguered Transbay Transit Center to reopen in July

Nine months after cracks were discovered in two structural steel beams of the Pelli Clarke Pelli Architects–designed Transbay Transit Center in San Francisco, the transit hub will finally reopen on July 1. However, busses won’t roll through the $2.2 billion terminal until the end of the summer; at first, only the 5.4-acre rooftop park will be open to the public. The repair plan announced in January appears to have worked, and, according to the San Francisco Chronicle, the building was declared safe by a panel of engineers yesterday. The Metropolitan Transportation Commission, which covers the entirety of the San Francisco Bay Area, had determined that welding access holes in the two cracked beams had been incorrectly cut during construction, resulting in stress fractures. After the city paid $6 million in testing and $2.5 million a month in security for the closed center, contractors decided to reinforce the two affected beams, and two untouched beams they connect to, with steel plates. Although the three-block-long transit center is safe to occupy again, the interior was stripped during the repairs and workers need more time to reinstall the ceiling and column coverings. Bus drivers, who had previously been picking up and dropping off passengers at a satellite terminal on Folsom Street a block away will need to be retrained as well. So in the meantime, fitness classes will resume on the transit center’s roof and pedestrians can once again explore the park. Still, there’s no news on the progress to bring rail to the complex’s basement, which was built to accommodate high-speed trains but remains empty. No timeline or budget has been agreed upon for a BART and Caltrain extension to the Transbay Transit Center, although politicians and the Transbay Joint Powers Authority, the independent agency responsible for bringing rail to the station, have agreed upon the need to do so.
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George Homsey, giant of California architecture, has passed away

George Homsey, one of the founding members of San Francisco–based firm Esherick Homsey Dodge and Davis (EHDD), has passed away. Widely considered a giant of California architecture, especially in the San Francisco Bay Area, Homsey practiced architecture with EHDD for nearly 50 years before parting ways with the firm in 2000 to run his own practice. During Homsey’s storied career, he worked with some of the greats of late-20th-century Northern California architecture, including business partner Joseph Esherick, and collaborators Charles Moore and William Turnbull. Together with these architects, Homsey helped bring to life Sea Ranch, the iconic shingled housing development situated on the rugged California coast north of San Francisco, as well as many delightful and contemplative private residences, schools, and public buildings. Homsey was regarded as the diligent and strong-willed counterpart to Esherick at EHDD, and helped to animate Esherick’s conceptually-driven works with a sensitivity to light, composition, and pragmatic materiality that made Homsey one of the fathers of what some called the “Third Bay Tradition,” a vernacular style of architecture that channeled and updated the Bay Area’s woodsy architectural and environmental influences for a new generation. Homsey, for example, was one of the chief designers of the hedgerow homes at Sea Ranch, a series of shed-roofed and wood-clad abodes that simultaneously struck out from and blended into the site’s scrubby terrain. Born in 1926 in San Francisco’s Western Addition, Homsey grew up in a typical San Francisco duplex where the modest units were separated by a pragmatic light well. The son of an auto mechanic, Homsey trained to become a naval aviator to serve in the military, but the war ended before he could take flight. With this training in hand, Homsey set out to study architecture at the City College of San Francisco and at the University of California, Berkeley. He joined Esherick’s fledgling firm in 1952 and made partner 20 years later. Homsey would go on to create the design guidelines for Yosemite National Park as well as comprehensive designs for San Francisco’s Bay Area Rapid Transit stations. He was awarded the Maybeck Award for lifetime achievement in architectural design by the American Institute of Architects, California Council in 2006 for his work.
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San Francisco’s largest homeless shelter is approved, but opponents vow to sue

After a GoFundMe duel that raised $101,000 for opponents of what could become San Francisco’s largest homeless shelter (and $176,000 for opponents of the opponents), the Embarcadero Navigation Center officially received approval from the city on April 23. However, even after a series of concessions between the city and opponents that the center would scale up to its 200-bed capacity from an initial 130 beds, and cut its operating life from four years to two (with an option to renew), opponents still weren’t satisfied. The SF Port Commission unanimously approved leasing a plot of land in the Embarcadero neighborhood to the city. Wealthy residents vowed to fight the shelter in court, after packing the hearing with orange, syringe-bearing signs that decried the “mega-shelter,” according to Gizmodo. Navigation centers differ from traditional shelters in that they allow pets, offer transitionary and health services, and allow residents to stay 24 hours; they’re also designed to be temporary structures. San Francisco mayor London Breed is pushing for the center at Seawall Lot 330, currently a 2.3-acre parking lot, to open before the end of the summer as part of her plan to add an additional 1,000 beds to the city’s capacity. It’s estimated that over 4,300 people sleep on San Francisco’s streets every night, and the city has become the most expensive to live in worldwide. Opponents have claimed that because navigation centers don’t allow drug use, the new residents will be doing drugs in public, and create an unsafe atmosphere in a neighborhood that welcomes a large number of families and tourists alike. Using the GoFundMe money raised, the shelter’s opponents, a group calling themselves Safe Embarcadero, have hired real estate attorney Andrew Zacks to fight the city. According to Gizmodo, Zacks claims that the city failed to deliver the relevant documents in a timely manner and will be suing. Meanwhile, the group presented a petition with 2,600 signatures at the April 24 hearing in opposition to the shelter. It seems that the courts will now decide whether the shelter can be built in time to meet Mayor Breed’s end-of-summer deadline.
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San Francisco homeless shelter inspires online fundraising battles

A homeless shelter proposed for San Francisco’s Embarcadero has resulted in dueling GoFundMe campaigns; one from residents who want to keep the Navigation Center out, and one to support the shelter. On March 4, San Francisco mayor London Breed allowed a plan to move forward that would transform a 2.3-acre parking lot in the eastern waterfront neighborhood into the city’s largest Navigation Center. Centers allow residents to stay 24 hours, provide health and wellness services, and allow pets—they’re also designed to be temporary. It’s expected that the center at Seawall Lot 330, if allowed to open by the end of this summer as anticipated, would only operate for four years while the city wrangles with its homelessness crisis. Some Embarcadero residents aren’t happy. On March 20, a group calling themselves Safe Embarcadero for All launched a GoFundMe campaign to raise $100,000 for a legal defense fund to help them oppose the shelter. Complete with its own website, Twitter feed, and well-heeled backers, Safe Embarcadero successfully hit its goal in 25 days. The group cited the large number of families and tourists the neighborhood draws, and the site’s potential proximity to landmarks such as Oracle Park as reasons for trying to push the shelter elsewhere. “The rushed process the Mayor is following to build the homeless shelter by the end of the summer is concerning to the community,” reads the Safe Embarcadero for All GoFundMe page. “We are worried that the rushed process puts the political goal of building a large Navigation Center ahead of legitimate concerns about public safety, drug use, and other problems that a large shelter may bring to the community. According to the city’s own data, a third of the homeless are drug users and some are sex offenders. “The Navigation Center will not allow drug use inside, meaning that about 75 drug users will be forced into the surrounding family neighborhood to use drugs. The community is also concerned about the environmental effects of building on a site that is known to have toxic materials beneath.” Perhaps recognizing that concerted opposition by “not in my backyard” organizers has killed or segregated low income and homeless housing elsewhere, a counter fundraiser was created in support of the Navigation Center. SAFER Embarcadero for ALL, citing the potential legal costs and community challenges that the shelter is facing, sought to raise $175,000 in support of the Coalition on Homelessness. With 1,900 donations, in comparison to the original group’s 360, that goal was reached in 17 days. The GoFundMe in support of the Navigation Center also drew big donations from Salesforce, Twitter founder Jack Dorsey, and GoFundMe itself, which contributed $5,000. The fight over the Embarcadero center is playing out in real-world meetings and protests that are just as charged as their online counterparts. On April 3, Mayor Breed was shouted down at a town hall meeting as she tried to stump for the scheme. While the mayor has proposed opening another 1,000 beds worth of shelters by 2020, so far only 212 have actually come online. The final battle over Seawall Lot 330 will culminate in a vote by the Port Commission on April 23, as the body (whose five members were selected by the mayor) votes on whether it will lease the site to the city.
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Sea Ranch comes alive in a new exhibition in San Francisco

The San Francisco Museum of Modern Art (SFMOMA) examines one of the earliest innovations in environmentally conscious development in its current exhibition, The Sea Ranch: Architecture, Environment, and Idealism. The show chronicles the history of the development at an extraordinary site along a ten-mile stretch of the Pacific Coast, where steep cliffs and coastal bluffs have eroded into layers of marine terraces to frame the luminous and moody ocean below. The story of Sea Ranch begins with the acquisition of the site by the developer, Al Boeke, who obtained the working sheep ranch for Oceanic Properties, a division of Castle & Cooke, a real estate company. Boeke, who had worked with Richard Neutra, was also an architect and saw an opportunity to do something different. He recruited Harvard-trained landscape architect Lawrence Halprin to develop the master plan, as well as a roster of architects, including Joseph Esherick, the firm of MLTW (Charles Moore, Donlyn Lyndon, William Turnbull Jr., and Richard Whitaker), Obie G. Bowman, and others to participate. Halprin’s master plan would not only define the design aesthetic for Sea Ranch, but would also challenge the cookie-cutter approach to planned communities that had emerged throughout the U.S. after World War II. Halprin, who had spent childhood summers on a kibbutz near Haifa, Israel, envisioned a community based on collaboration and shared community. People would “live lightly on the land,” as the indigenous Pomo people, the first inhabitants of this land, did. The curators of the exhibition included photos of dance workshops choreographed by Halprin’s wife, the modern dance pioneer Anna Halprin. These photos, combined with Halprin’s diagrams of the “Sea Ranch Ecoscore,” situate the development, in part, as a period piece of the 1960s, echoing a freewheeling West Coast lifestyle. However, the exhibition clears up any misimpressions of Sea Ranch as primarily a social development with utopian yearnings, making clear that its main subject has always been design and its relationship to the land. If a certain taste and ideas about light, color, and detail distinguish the Sea Ranch design, it is because these were born out of the designers’ sensitivity to climate and place. The slope of a shed roof deflects the wind, and a courtyard creates protected shared spaces. A bay window protrudes to capture a view, and hedgerows are planted as natural wind breaks. The meadows are left open, and houses are set back from the edge of the cliffs, creating a communal landscape. Details matter too. Buildings are clad in unfinished wood that is allowed to fade to natural gray. Skylights puncture the roofs of cabins to capture sky views of the redwood forest. Donlyn Lyndon noted, “We wanted to make buildings part of the land, rather than buildings that sat on the land.” Sketches, drawings, and pages from the designers’ notebooks line the walls and tables of the gallery. These works include the original master plan and concept sketches by Halprin and work by the architects, such as Joe Esherick’s scheme for the General Store and MLTW’s plans for the modules for Condominium One, conceived of as a kit-of-parts. Scale models of Moonraker Athletic Center, Unit 9 in Condominium One, Cluster Houses A, and the Hedgerow Houses were fabricated by architecture students at the University of California, Berkeley. At the center of the gallery, a 1:1 scale partial construction of Unit 9 of Condominium 1, designed by MLTW in 1965, has a soaring loft, built-in benches, and a sleek but cozy feel. It is easy to imagine an afternoon stretched out on the long bench with a book, looking out at the churning sea. Inside the mock-up, a video presents interviews of many of the original players. Donlyn Lyndon, Mary Griffin, Obie Bowman, Anna Halprin, graphic designer Barbara Stauffacher Solomon, and others recall their impressions, debating whether the dream was deferred or lives on. Hard lessons were learned. A growing awareness of coastal access emerged in the early days of the development. Negotiations followed between the developers and the newly formed California Coastal Commission. The Sea Ranch ceded land to create six public trails. This fight stalled momentum for a decade, and the project shrank in size from its original plat map for 5,200 individual building sites to around 1,700. As a result of the complications around coastal access, sales fell off. Critics saw the development as out of touch, elite, and fuel-intensive, as it is accessible only by car along Highway 1. Getting there meant driving or maybe flying, and once there, there were few retail shops or services. In the video, Lyndon noted, “The myth is that it fell apart, which isn’t entirely true. The truth is that it needs reaffirmation…” The reaffirmation may have appeared in the form of this exhibition. As a powerful and immersive museum experience, a moment in American architecture is captured when ideology, talent, and opportunity converged. Once seen, it would be difficult to dismiss the poetic quality of the Sea Ranch site and the elegiac response of its developers and designers, who allowed the nature of what is there to take form. While setbacks may have colored its utopian vision, they did not negate the project’s importance in the pantheon of American design. From Sea Ranch, designers will continue to glean lessons about building within landscapes, respecting and protecting the natural character of a place, and designing houses that suit their sites, climate, and inhabitants. The Sea Ranch: Architecture, Environment, and Idealism is on view at the San Francisco Museum of Modern Art, through April 28, 2019.
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Cracked glass discovered at Salesforce Tower in San Francisco

A pair of cracked windows have been discovered at San Francisco’s Salesforce Tower. It's another stroke of bad luck for the city's newest architectural marvels. The San Francisco Chronicle reported that local Department of Building Inspection officials confirmed the presence of cracked window panes in the 61-story, Pelli Clarke Pelli-designed tower last week. The cracks were discovered along the inner panes of a dual-glazed, south-facing window on the 12th floor and a similar east-facing window on the 14th floor of the tower. A spokesperson for the building’s owner told CBS in San Francisco that because the cracks are located on the inside of the window assembly, the damage poses no danger of falling glass. The cause for the cracks has not been discovered, but plans are underway to replace the affected windows in the coming weeks. The Salesforce Tower opened in January 2018 and is currently San Francisco’s tallest building. At 1,070 feet in height, the building is considered the second tallest structure in the western United States behind Los Angeles’s Wilshire Grand tower. The discovery of cracked windows at Salesforce comes months after broken window panes were discovered in the Handel Architects-designed Millennium Tower just one block over. The 58-story tower has settled over 18 inches on one side and is also leaning by 14 inches, according to recent reports. The settling is believed to have caused the cracked windows discovered last year at the tower. Plans for a $100 million fix to stop the sinking are currently under development. Those efforts include drilling up to 300 new micro-piles through the building's foundation and into the bedrock below in an effort to stabilize the tower. The tower opened in 2009 and cost about $350 million to build. Another new San Francisco project, the Transbay Transit Center, located at the base of the Salesforce Tower, remains closed nearly six months after a pair of cracked structural beams were discovered in that building. A permanent fix for the damaged beams is currently underway, though a reopening date for the transit center has yet to be announced. Officials with the Transbay Joint Powers Authority blame manufacturing defects for the damaged beams. These troubles come as news of the city’s precarious subsoils and the potential earthquake risk for certain high-rise towers are brought to light as well.
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Facades+ San Francisco will dive into the Bay Area's exciting technological trends

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The San Francisco Bay Area is nourishing one of the country's most active architecture scenes. Fueled by a booming technology sector, rapid population and commercial growth are delivering exciting new projects to the region. On February 7, The Architect's Newspaper is gathering leading local and California-based design practices for Facades+ San Francisco, a conference on innovative enclosure projects across the city, state, and country. Participants include EHDD, BuroHappold Engineering, CallisonRTKL, CO Architects, Heintges Consulting Architects & Engineers, and David Baker Architects. Joe Valerio, founding principal of Valerio Dewalt Train Associates (VDT), will co-chair the half-day symposium. AN interviewed Valerio about what VDT is working on and the firm's perspective on San Francisco's architectural trends. The Architect's Newspaper: San Francisco is arguably the nation's leading technological hub. How do you see this role impacting the architectural development of the city, and what do you perceive to be the most exciting facade trends in San Francisco today? Joe Valerio: Perhaps, the pressure that technology companies are creating on the building sector will finally lead to real innovation in how we build things. The San Francisco building sector does not have the capacity to move forward using conventional means. I believe that continual innovation will help the city catch up to its vast demand. It’s an exciting time for design in San Francisco. With technology evolving at such a rapid rate, it has been interesting to see how it is beginning to manifest itself in architecture, both physically and experientially. For instance, in the physical sense, buildings like the de Young Museum or the Transbay Terminal are utilizing parametric modeling to create interesting forms and textures with metal mesh. Faceted glass is also being implemented in interesting ways in high-rise projects, such as the LinkedIn headquarters or the Oceanwide Center. But on the experiential side, digital is becoming a new palette for architectural design. The Salesforce lobby, for example, uses digital projection mapping to draw people in from the street. Its translucent facade almost disappears from view, making the lobby feel like its extension. This is something that we have been experimenting with in our own work, in projects such as Art on theMart in Chicago or the YouTube lobby in San Bruno. What projects is VDT working on, and what innovative enclosure practices are being used? JV: We are developing a graduate student village for Vanderbilt University in Nashville, with our partners at Lend Lease Communities, and are looking at a wide range of modular and prefabricated construction techniques to meet the speed at which we need to deliver this project. New modular techniques that implement cross-laminated timber and steel into their modules are allowing us to go higher than the five stories limited by wood stick construction. We’re also implementing modular prefabricated cold-formed steel panel systems for quick assembly on site. Universities present tremendous opportunities in housing, and we find that embracing challenging parameters leads to very exciting outcomes. VDT is located in multiple cities across the country; what are the particular challenges and benefits of working in San Francisco? JV: One of the most exciting aspects of working in San Francisco is our client base. We work with companies that are constantly pushing the boundaries of technology, and for us, finding new ways to meet their needs with architecture is a thrilling prospect. Quite often, our work in the city deals with very interesting pre-existing buildings, such as in the case of Adobe Town Hall. Here we were challenged to both expand and reinvent the company’s dining experience all the while preserving a building that’s listed as a historic landmark. Its previous function as a tool factory became the driving force behind a new design, conceptually celebrating culinary tools developed by their new chef, and digital tools that Adobe continues to develop to this day. It’s opportunities like this that constantly pique our interest in San Francisco. But on the other side of the coin, having such a highly innovative and skilled architecture community has created a severe labor shortage in the city—a constant reminder of how thankful we are to have such a talented team. Is there a particular technique or materials that VDT is experimenting with? JV: There has always been a drive to bring new materials into our enclosures. Yet these systems are still dominated by old techniques and primitive materials such as glass. We have experimented with new materials such as ETFE, and we would forecast that assembling these old materials in innovative ways is the path forward. Remember the iPhone has a glass screen. Additionally, cross-laminated timber (CLT) continues to show a lot of promise. We have been working with a company on modular prefabricated CLT housing at a larger scale, and we’re excited to see how we can begin to leverage cost and design with new techniques. Further information regarding Facades+ San Francisco may be found here.
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Repair plan for shuttered Transbay Transit Center is in the works

Late last week, Transbay Joint Powers Authority officials in San Francisco approved plans to repair a pair of fractured beams that were discovered at the now-shuttered Pelli Clarke Pelli Architects–designed Transbay Transit Center last fall. The plan calls for the installation of four sets of new steel reinforcing plates to shore up the failing members, The San Francisco Examiner reported. The peer-reviewed repair plans were approved in late December by the Metropolitan Transportation Commission (MTC), a transportation agency that works across the nine-county San Francisco Bay Area. MTC’s preliminary investigation concluded that the issues with the fissured beams were linked to the presence of welding access holes that had been cut into the beams to facilitate their installation. In all, four beams will be reinforced under the repair plan: the two fractured beams spanning over Fremont Street and a pair of corresponding but uncompromised beams located on the opposite side of the building. According to the report, the steel plates will be bolted together above and below the areas where the fractures occurred on each beam. A date for reopening the center has not been set, but authorities are at work on a construction schedule for the repairs. A further update to the plans will be presented to the board of the Transbay Joint Powers Authority later this week. The $2.2 billion transit center opened to much fanfare in August 2018 but closed just a few weeks after its debut because of the construction faults. The transit center spans three blocks and is capped by a 5.4-acre park designed by PWP Landscape Architects. Thornton Tomasetti is the design engineer for the project. The center has been closed for over 100 days and commuters have gone back to using a temporary bus depot that had been in operation during construction for their daily transportation needs.
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San Francisco orders historic Neutra home be rebuilt after being torn down

Preservationists in Twin Peaks, San Francisco, were aghast this past December when it came to light that much of a 1935 home designed by Richard Neutra had been illegally demolished months prior. Owner Ross Johnston had purchased the 1,300-square-foot 49 Hopkins Avenue—also known as the Largent House—for $1.7 million with plans to replace it with a 4,000-square-foot mega-mansion in 2017. Only the home’s garage door and frame still stand today, but on December 13, the City Planning Commission unanimously ruled that Johnston must build an exact replica of the house, as well as a plaque detailing the building’s history. The Largent House was one of only five buildings designed by Neutra in San Francisco. The two-story, whitewashed-concrete-block and redwood-timber building made ample use of glass bricks to let in natural light and included a greenhouse-like glass topper to enclose an indoor pool. The plague of illegal demolitions by San Franciscan homeowners hoping to build big or flip the property is widespread, and punitive repercussions are rare. The city is in the middle of a housing crisis, and when faced with the option of forbidding offenders from building on the demoed lot, the Planning Commission has let homeowners off the hook. Not this time. Johnson applied for a demolition permit and permission to build his new house two months after the home was razed, arguing that a fire in 1968 and remodels throughout the 1980s and ’90s had removed the home’s architectural significance. Rather than flipping the plot of land, Johnson claims that he was only building something that could accommodate his six-person family and that the demo was undertaken for safety and quality of life reasons. The Planning Commission disagreed, and in a 5-0 vote, ordered Johnson to rebuild the Largent House. Planning Commissioner Dennis Richards hopes that the move, along with the recently proposed Housing Preservation and Expansion Reform Act, which harshly penalizes illegal demolitions, would help curb speculation in the housing market. “The fact that it was a unanimous vote should send a message to everyone that is playing fast and loose that the game is over,” Peskin told the San Francisco Chronicle. “We want to preserve iconic, historic structures, but even more important, we want to protect our reservoir of more affordable housing stock. You want a 1,300-square-foot house to be worth what a 1,300-square-foot house is worth, rather than a mega-mansion.” Unfortunately, this isn’t a shocking story in 2018, as a number of architecturally significant homes, including a Venturi Scott Brown–designed house in Pittsburgh, faced under-the-radar demolitions and renovations.
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Possible source of failure discovered for San Francisco’s Transbay Center

Nearly three months after a pair of cracked steel beams were discovered at the Pelli Clarke Pelli–designed Transbay Transit Center in San Francisco, crews investigating the structural failures have begun to piece together what might have gone awry. According to recent investigations, the beams in question were not only fabricated with imperfections that rendered the steel more brittle and weaker than specified, but they were also altered by the fabricators before they were installed in a way that differed from the shop drawing designs that had been initially approved for the project, The Mercury News reported. The changes include the addition of so-called “weld access” or “weld termination” holes along the web of each joist to make installation easier. While it is still unknown exactly which type of openings were made in the beams—there are key design differences between the two types of holes—the resulting change is thought to have created an imbalance in how the loads from the building above were delivered down to the transit center’s foundations. As the center came under regular use, the buses and crowds that occupied its upper levels put enormous strain on the compromised beams, resulting in the debilitating fissures. The Mercury News reported that Stockon, California–based Herrick Corporation, the company responsible for fabricating the steel beams in question, prefers to refer to the openings as “weld termination” holes because those openings are less strictly regulated than “weld access” holes, which have more stringent design and finishing requirements. Design engineers Thornton Tomasetti have not provided comment regarding the nature of the openings in question. Robert Hazleton, president of Herrick Corporation told The Mercury News, “It may sound like a small thing, but it does change how you finish the inside of the hole,” adding, “There are less specific requirements for a weld termination hole.” The stresses resulting from the new openings compounded the inadequacies of the steel members, according to the report, which also highlighted a lack of specificity regarding these types of failures in San Francisco’s building codes as a key oversight in the building’s design. Potential fixes for the beams include welding supplemental steel plates to each member to improve their rigidity, though the Transbay Joint Powers Authority, the public agency tasked with building and maintaining the terminal, will not have a specific plan for repairs or an estimated date for reopening the $2.2 billion complex until January 2019. Until a final cause and remedy are found, San Francisco commuters will continue to use the temporary bus terminal created during construction of the Transbay Center for their transportation needs.